Can you run an A wide open?

[29RPU]

I hear stories about guys racing a circle track in the old days with the pedal to the floor. Another one talked about "runnin 'er wide open, I could get to 54 mph". I suspect this isn't good on an engine, but how safe is it to run the pedal to the floor on model A engines? Can they be over reved that way, or are they not able to reach a critical RPM? Just curious what you guys have done and what the consensis is.

[Kevin in NJ]

Depends

A factory engine was carefully balanced and would go over 60 mph. So an engine brought back to factory specs should have little troubles.

Babbitt is a bearing that let's the crank spin. The enemy of Babbitt are conditions that let the Babbitt be pounded. Out of balance and lugging are the two conditions you need to avoid. Running high rpms with a balance system is a good condition.

Finding a properly balanced engine today is another story. Many A's are not well balanced and will beat themselves up at high rpm.

[Special Coupe Frank]

My tired, mostly-original 81,000-mile '28 Special Coupe will do about 58 MPH, flat-out, on level road, dead-calm or with the wind behind it. Speedo might be reading 5 MPH "fast" at that speed.

That's about 2300-2400 RPM, doing the math against the 3.78 rear and 4.50x21 tires.

A lighter body will achieve a slightly faster top-speed ( all other aspects being equal): a Roadster is probably lightest / quickest, a Sedan or Wagon would be the slowest, due to weight. A speedster with completely stock running-gear might achieve 75 mph or better ?

Running "wide-open-throttle" with no load on the engine may push it into self-destructive territory.

Apparently, one of the self-limiting factors of an original A is the "breathing"... the original Zenith carb and updraft intake are considered to be fairly restrictive, and that has a limiting effect on top-speed / max RPM. Probably keeps the stock A at or below the danger zone.

Some guys like to bore-out the intake throat of the stock manifold to gain better breathings and a little more speed.

As far as the babbit bearings go, poured babbit bearings are best for "rotating applications" - main bearings, line-shaft bearings in factories, pillow-blocks for band-saws, etc...

Applications where there is reciprocating or percussive load ( rod-bearings ) tend to have a shorter life. Excessive bearing clearance accelerates damage, by allowing the bearing to be "pounded" each time the reciprocating assembly stops and changes direction.

If you want to learn more about this aspect, find a copy of the "Auto Math Handbook", and study the section where they discuss "piston travel speed" and "reciprocating mass" and its effects on rod and wrist-pin bearings. The reciprocating assembly has to come to a complete stop and reverse direction twice for every revolution of the crankshaft... start winding-up the engine, and those forces can become destructive.

Also, the gravity /splash oiling system of the A may not be sufficient for sustained flat-out running...

I try to keep my speed at 50 MPH or less.

"Back in the old days", Model A's were common and cheap; if the boys blew-one up on the dirt track, they could go get another for $15-$25 and go flog that one...

Not the case anymore...

[Jerry Parr WI]

I don't make a habit of it any more but I have run my dead stock 30 coupe flat out for extended periods. Tops out in the low 60's.

[Larry Brumfield]

Henry Ford wrote about the Model A:

"The new Ford will ride comfortably at fifty and sixty miles an hour. It has actually done sixty-five miles an hour in road tests." Henry Ford
---------------------------------

With all other things in good working order as original, all it would take is a supply of NOS original camshafts and the speeds above would easily come back to life.

Larry B.

[Bruce in southern OH]

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Always a good rule to live by when you drive an A, Don't drive faster than your ANGEL can FLY!!!!!!!!! Bruce

[J Franklin]

Oiling starts to become iffy after 45 MPH I was told by a respected engine builder who knew a bunch. Used to just go to the dealer for a rebuilt engine installed for a few dollars, so why not run it flat out? Oh yeah those old dirt roads kinda slowed you down

[Larry Brumfield]

The respected engine builder's work must have been "iffy" after 45.


Larry B.

[craneygartz]

As far as the babbit bearings go, poured babbit bearings are best for "rotating applications" - main bearings, line-shaft bearings in factories, pillow-blocks for band-saws, etc...

If you get a chance, read about Harry A. Miller's 91 CID straight 8s running Babbitted rods and mains at near 8000 RPM for long enough to win Indianapolis multiple times in the mid twenties.

John

[LeroyM]

I have a Model B motor in my 31 coupe. It's a diamond block with 0.60 over bore, Snyder's high compression head, Ansen downdraft intake with a Stromberg 97 carburetor, Mallory distributor, 38lbs lightened flywheel, backed by a 39 transmission. I'm running 700x16 tires on the back and I'm guessing the rear is 3.78, but I'm not sure. On a nice open stretch of highway I can bury the speedometer which is 75mph and that's holding it to the floor.

My goal is 100mph some day. They use to set land speed records with them in the late 30's and 40's and run 130 to 140 mph. Running wide open isn't good for them, but every once in awhile I don't see why it would hurt.

[Tom Wesenberg]

Put 4 bends into a coat hanger so it is the same shap as the Model A crandshaft and run it in a drill at 2,000 RPM and see what happens. Wear a leather glove to support the outer end, just as a Model A bearing would support the crank. The Model A crank is just a large bent wire. Without counterweights the Model A crank acts just like that bent wire and the bending forces are squared as speed doubles. I like to keep my speed 45 and below and will probably do the same even after I add counterweights.

My cousin inherited her dad's very nice original 41 Chevy 1 1/2 ton truck, which her dad bought new. She lent it to some fool that thought he should be able to drive it 65 on the freeway. He put a rod out the block and after setting untouched for 10 years, it finally went to the scrap yard.

A fool and his toys are soon parted!

[Marco Tahtaras]

Originally Posted by J Franklin

Oiling starts to become iffy after 45 MPH I was told by a respected engine builder who knew a bunch. Used to just go to the dealer for a rebuilt engine installed for a few dollars, so why not run it flat out? Oh yeah those old dirt roads kinda slowed you down

It sounds like he needed an excuse for bearing failures. I've done thousands of miles over 60 mph without a hint of bearing problems or even having to take up for wear on the bearings.

[Art Bjornestad]

There is an old saying that the road to Las Vegas was paved with Chevy connecting rods.

[Freddie (Memphis)]

Originally Posted by 29RPU

Can you run an A wide open?

Sure...for a little while.

[Purdy Swoft]

Tom, really. With all due respect there is no comparison with a coat hanger and a model A crankshaft!!!!!!! We like to cruise on the highway at 50mph, any slower and we may get ran over. If everything is in good condition 50 mph won't hurt.

[Chris in CT]

Originally Posted by Bruce in southern OH

Always a good rule to live by when you drive an A, Don't drive faster than your ANGEL can FLY!!!!!!!!! Bruce

Hi Bruce, I love it. That would be true for any vehicle, really.
Yes, you can run a "good" model A under load wide open. Thus damped, the engine will not over-rev with its stock cam and carb.
I had my own 29 roadster (b cam, 5.5 head, and Burlington crank) up to 70 mph just for a test, but I got nervous when I realised that I might be outrunning my Angel! LOL

[roccaas]

Also remember that your skinny tires are put on BY HAND. I've been to 65 mph and seen my life flash before my eyes when the crosswind hit! Oh yeah, mechanical brakes, that might give you pause.

[Larry Brumfield]

As mentioned in my post above, even Henry Ford implied that one should not run the Model A wide open, i.e., 65 miles an hour as in road tests.

Now do any of you think that Henry Ford himself would have made a statement about comfortable driving at 50 to 60 miles an hour if the Model A was going to throw rods or come apart? ....

Naturally, if your Model A has thicker babbitt and a crankshaft ground down so many times it's about like a toothpick, OR high mileage with shims removed OR unknown condition of bearings from a lot of use, it's best to putt putt 45 in your Model A.

BUT, as it was when Henry made it, the Model A was made to run! Wouldn't Ford have lost his credibility if the Model A engines had come all apart shortly after purchase.... "Sorry, you shouldn't have gone over 45."

The crankshaft whipping and worn out center main didn't happen overnight either. People drove them for miles with no problems.

All this reminds me of a statement a friend made to me 31 years ago when I first got into Model A's. My friend, who was a grown man when the Model A was new and a mechanical engineer, said that if the men alive back then could come back and watch how many of the Model A'ers drive today, they'd laugh!


Larry B.

[Louis]

Yep!...but, stupid is as stupid does .

[Old182]

I've had my coupe for 50 years this year and when I was in high school I used to power-shift it, run it up hills until the exhaust manifold glowed, and rode it down Storm King Mountain near West Point NY at full bore (well over 65!). That was then. After new bearings in 1962, and a complete restoration in 1988, we feed it ice cream these days. I'll go 50 if forced, but 45 is generally my limit. It's not that the car won't do it, it's more a case of preserving the engine. I have no intention of possibly harming a good engine because some guy in a Honda or BMW is in a hurry. BTW, I still have the top half of the transmission case and cluster gear pieces in my barn as reminders that these cars can take much abuse, but not for a steady diet.

[29RPU]

Thanks guys! Pretty much as I figured, and I sure enjoy the input. I hadn't thought about the ease of block replacement 'in the old days' as opposed to preservation now. That really makes a lot of sense regarding the disparage of treatment 'then' vs. 'now'.

I have wanted to push my speedometer a little more than 45, but I have a bit of vibration on deacceleration. I have come to understand this is somewhat normal, but still makes me a little nervous. I might push it a tad more and see what happens.

It is a little difficult coming from cars of the 60's. I've had my 69 camaro over 130 (way faster than my angel can fly). I realize I can't have nearly those expectations from model A's and just seek to find where that line lays!

I just wanted to jump in and say thanks, but please keep the input coming as long as it stays interesting.

[Kurt in NJ]

I have been testing my babbitt job for 25 years, started out for the world meet in 86 with fresh babbitt, left with 40 miles on it from the night before, got on the turnpike at Harrisburg, kept it to a little over the minimum speed, thought I was slowing down too much in the mountains before Ohio, but then started passing Toyotas, hondas etc., decided I wasn't doing so bad. Stopped for the night in Ohio, when I shut it off it rocked on compression, changed the oil, the next day I found my terminal velocity--67 mph. Kept it to 55-60 the rest of the way to Wisconsin ---except through Chicago, there I soon found that it was safer to drive faster than the merging traffic.

I got my Blue ribbon, but did not enter fine point judging.

On the way back to NJ I tried to break it, I traveled most of the way at 65, averaged 23 mpg, changed 1 condenser, no other problems.

In the late 90s I lost the babbitt in a rod ---very suddenly, at 65 mph, I slipped a replacement in from the bottom, but it was something like 14 grams heavier, I lost 5 mph top speed, gained some more vibration.

Now I have slowed down some, I don't pass as many cars on the highway, keep to 55-60 on the parkway.

My car is stock except for a B cam, a diode in the cutout, and halogen headlight bulbs.

[jetmek]

back in the day you could get junkyard a engine that ran good for 10 bux also....much easier to replace when it blew

[Larry Brumfield]

Old 182, there's quite a difference between deliberately trashing a Model A with speed shifting, etc. and driving a sound Model A in a smooth manner at speeds which it was designed to be driven. Even Louis Gump above might be able to grasp the thought.

I for one don't care to risk my life getting rear-ended and possibly killed by the modern day driver. Nor do I care to yield to the modern day driver and spend my drive on the shoulder of the road allowing my tires to pick up all the roofing nails, wood screws, bits of glass, etc. that always seem to wind up there.

Just my opinion.

Larry B.

[Special Coupe Frank]

Originally Posted by Larry Brumfield

Henry Ford wrote about the Model A:

"The new Ford will ride comfortably at fifty and sixty miles an hour. It has actually done sixty-five miles an hour in road tests." Henry Ford
---------------------------------

With all other things in good working order as original, all it would take is a supply of NOS original camshafts and the speeds above would easily come back to life.

Larry B.

For how long ?

I'm not out to knock Ford's engineering... but... until the Pennsylvania Turnpike was opened in 1940, there were no long-distance high-speed roads... I don't think many Ford buyers had the wherewithal to test Old Henry's claim...

There may have been some exceptions out in the flat Mid-West, and Southwest.

I have no doubt that an A in good factory spec can achieve 60-65 MPH; I'm still skeptical as to how long it will do so on a continuous basis...

Were there any Ford High-speed endurance runs along the lines of those by Cannonball Baker or Ab Jenkins ?

And what was considered to be the accepted mileage-life of an automobile engine in 1930 ?

I'm for erring on the side of caution; 50 mph is probably a safe maximum cruising speed for the average Model A....

[Ken/SC]

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I have always told people, its not how fast a Model A will go, its how fast it will stop!

[Special Coupe Frank]

Originally Posted by Ken/SC

I have always told people, its not how fast a Model A will go, its how fast it will stop!

An extremely valid point... especially if driving in rainy weather...

I drove home from work after a heavy rain the other day and was alarmed at the loss of braking efficiency due to wet linings...

I was running late for a meeting this morning, and had my '28 maxxed-out... foot to the wood for most of my trip (25 miles)... almost saw "60" on the speedo...

[MrTube]

From what i've gathered from this thread it seems perfectly fine to run a properly running 'A' wide open. The fact things will wear faster is a given, this goes for any machine.

how long does the typical A engine last before a rebuild? I think the one here has just under 60K on it.

[Larry Brumfield]

Special Coupe Frank,

Do you read or do you just call words?

I said, "With all other things in good working order as original ..."

Now what do you think that means???

Naturally, the condition or working order of the engine or anything else would only be known by the man who owns the car ... IF he cares to make that determination. Otherwise, he'd be an idiot to drive the car at higher speeds.

For how long you say....

About 40,000 miles on an engine, more or less, was a long way in the 1930's with rougher roads full of dust and the oil of the day. But not today .... even for a Model A. I have customers reporting as much as 60,000 miles of trouble free operation AND STILL GOING STRONG with nary a loose bearing running high compression heads!! ...

But like I said, it's just my opinion. You drive your car any way you want to.

Larry B.

[Old182]

I hear ya, Larry. Sometimes kids do dumb stuff. I had the good fortune to be able to store the car in a barn until I grew up a little and was able to do a proper (albeit amateur) restoration on the old gal. She now gets the respect she deserves (God knows, she paid her dues!).

[Logan]

I run my coupe pretty much wide open almost everywhere I go. I put It on the floor when I leave stop lights and don't let off when speeding up. I also run in the fast lane on the interstate everywhere I go. Yes I have a 26% o.d but I'm not going to say how fast my average speed is. Let's just say the engine is doing well over 45 with the od factored in and I don't put it in o.d. Until 55-60. The engine is all stock, babbit bearings and has 30000 miles on it. The engine won't last as long at high rpm but it is safer to run faster with traffic. I don't know about the rest of you but I would rather buy a new engine than have to do an @ss load of body work to fix a smashed up rear end from getting run over.

[pat in Santa Cruz]

Originally Posted by MrTube

given, this goes for any machine.

how long does the typical A engine last before a rebuild? I think the one here has just under 60K on it.

My S/W had 72K miles on it when I got it. I took the last shims out of the one loose rod to tighten it up and drove another 6000 miles before I pulled it to rebuild it. The crank pin was no longer round so the bad rod wore more quickly. The engine was the original matching numbered, std pistons, std bearings, Ford script valves, all Ford parts engine with a Police head.

[skip]

I don't worry about the churn coming apart wide open as much as the two blade fan coming apart and going through something. Having said that...

" I Drive As If I Had A Raw Egg Between My Foot And The Accelerator Pedal. "

Nothing kills an engine more than rpm changes. Slow and steady. Baby her. Double clutch and wait for things in the transmixer to slow down or catch up. A blip on the throttle for up sifts and smooth as silk engagements .

My self imposed limit on speed is 45 mph. Fast enough. I did go to 53 mph once just for poops and grins.

Can you run an A wide open? Sure right up to when it comes apart.


skip.

[Old182]

It's interesting how diverse we all are regarding this subject! We have folks in our club who run their As at 65 on the highways and have no problems (as many who've posted here). We also have a few who prefer about 35 (which can easily get you killed these days), and then there are those of us who who prefer something in between. I guess I just like the back roads over highways and if I need to get somewhere fast, I don't take the old bugger. BTW, Larry, I get out of tailgaters' way even in my modern car - I don't know about your neighborhood, but the aggresive drivers here in NY are not affraid to die proving they're better than you.

[skip]

I really get a kick out of the drivers at red lights who creep up on the light to make it change faster. LOL. Our town has timers, but not magnetic in road pick-ups.

skip.

[MrTube]

"I really get a kick out of the drivers at red lights who creep up on the light to make it change faster. LOL."

Depends on if your over the inductor in the road or not. If your not over the inductor the light may never change. I have a feeling most people don't realize what changes the light and just think creeping forward does? I always make sure to stop my car right over the inductor or at least with the engine over it.


I personally only creep if I had to come to a long hard stop and know I heated the rotors up something awful. Or in my old chevy pickup i'd keep it rolling some so I didn't wear the clutch as much taking off. Whether or not it matters i'm not sure but had I 190K on the clutch before putting a new one in.

[bobpo]

My Father-in-Law was pulled over by he Highway Patrol for driving too slow, 40 MPH. (55 mph zone). The trooper told him that the patrol had received three (3) complaints about his low speed. This was on a 4 lane highway with a turning lane in the middle. This is also a heavy traffic stretch of roadway this time of the year. My father-in-law said, O.K., I'll drive faster. The Trooper then let him go........

My Father-in-law is 92 years old and the speed limit is 55 MPH.

I guess he thought he was back in that Model A he always talk about.

[Special Coupe Frank]

As for "driving too slow", if your machine can't keep-up with traffic, you need to find a slower road.

My '28 coupe might make 58 -60 mph by the speedometer ( which I suspect is about 5 MPH "fast" at that speed), on level road, as long as there's no head-wind.

The "average speed" on the Interstates / divided highways around here ( NE Penna) is 75-85 MPH, regardless of the 55 MPH posted limit.

It would be suicidal to take my Model A out on a congested road where my top speed is 20 - 30 MPH below the average flow of traffic, even if it is achieveing the legal, posted limit.

I don't even like to take my "modern" '41 De Soto out on the Interstate... it's too punishing to the vehicle to try and keep-up with traffic.

I have several choices of "milk-route" to get me where I'm going.

There was a tragic accident on MD I-70 in Howard County the other year, where a father and daughter were killed when their Model A pick-up was rear-ended by another motorist... when my Mother told me about it, my first words were " what the h__ was someone doing driving a Model A on I-70 ???!!!".

I used to try to drive that stretch of highway in my Grandad's '54 Chevy pick-up 3/4 ton, 4.57 rear) when I was in high-school... that was crazy 30 years ago...

Congested Interstates are no place for the Model A, in my opinion; I don't care how high your CR is, what carb, OD or what have you... modern traffic conditions push you too close to or past the safe operating limits of the machine. Limited tires, brakes, suspension... plus every other driver around you who is distracted by cel-phone, stereo, GPS, etc. Just not a good idea.

Now, if you've got miles and miles of deserted highway, that might be another story; that doesn't exist in my neck of the woods.

[J Franklin]

If the traffic on your inter-states are usually 20-30 MPH over posted you should charge the overseers with malfeasance and demand they bring traffic under control. Why do we pay taxes?

[MrTube]

Here in NJ you'll see 55-65 in right lane, 75+ in center lane and 85+ in left lane on most major highways such as the garden state parkway and 287.

Honestly I don't mind the speeds people drive, what I do mind is they feel its necessary and safe to drive 1 car length away from the person in front of them doing these speeds. I've constantly seen 5+ car accidents because everyone was following 5 or 10 feet from the car in front of them going 75+ and the front person had to stop fast.

The even more amazing thing is people will drive past an accident like this, and then resume doing the same exact thing!!!!

I'll admit, i'm 29 and have a lot to learn in life. But I had enough near death accidents on ATV's long before I was old enough to drive a car to realize how fast things happen when your doing in excess of 65mph. Things happen literally in a blank of an eye.

I think modern cars make people feel to safe when they really are not. People need to realize just how fast 1 mile a minute truly is.

[Special Coupe Frank]

[QUOTE=MrTube;35764]Here in NJ you'll see 55-65 in right lane, 75+ in center lane and 85+ in left lane on most major highways such as the garden state parkway and 287.

Honestly I don't mind the speeds people drive, what I do mind is they feel its necessary and safe to drive 1 car length away from the person in front of them doing these speeds. I've constantly seen 5+ car accidents because everyone was following 5 or 10 feet from the car in front of them going 75+ and the front person had to stop fast.

The even more amazing thing is people will drive past an accident like this, and then resume doing the same exact thing!!!!

I'll admit, i'm 29 and have a lot to learn in life. But I had enough near death accidents on ATV's long before I was old enough to drive a car to realize how fast things happen when your doing in excess of 65mph. Things happen literally in a blink of an eye.

I think modern cars make people feel to safe when they really are not. People need to realize just how fast 1 mile a minute truly is.[/QUOTE]


You mean, people should think about what they are doing, consider the consequences, and take responsibility for their actions ????

Modern society is becoming increasingly detached from the activities of everday life ( everything is passive, done for us at the touch of a button, click of a mouse..)... we don't have to THINK about what we are doing; and therefore, we don't.

More and more, we ( the nice polite, "sane", thoughtful people) have to watch-out for "the other guy" who is oblivious to everything and everyone around him / her.

The other aspect of driving a Model A ( or other vehicle from that era) in modern traffic and/ or at high speeds is that our cars offer very little in the way of crash-protection... if we are driving along at the posted speed limit ( say 55 mph ) and some distracted driver in a late-model Volvo ( or other highly safety-rated vehicle of your choice ) plows into us, "everyone loses", but chances are, the occupants of the newer car walk away, or go to the hospital to be treated for relatively minor injuries. The occupants of the vintage car are much more likely to suffer mortal injuries.

It's kind of like being in a jousting match without any armor, having a stick for a lance, and a stick-horse instead of a beefy charger... the other guy is going to destroy you ! ( Sorry - don't know where the heck that analogy came from... too much Monty Python, I guess )

I'm not about to stop driving my antiques, nor do I wish to "take all the fun out of it" for anyone else... but when we talk about running the A wide-open, there's a little more to it than just "not blowing-up the engine"...

Modern cars are technological wonders; modern drivers ( for the most part ) stink.

Be careful out there...

[Larry Brumfield]

Originally Posted by J Franklin

If the traffic on your inter-states are usually 20-30 MPH over posted you should charge the overseers with malfeasance and demand they bring traffic under control. Why do we pay taxes?

Mr. Franklin, that's exactly right.

On the interstate, whether it is congested or not ..... the right lane is for the slower drivers and people are supposed to respect it!! ... slow being a little over 50 to about 65 in Texas.

Moreover, even on the so called milk-route you run the risk of some baggy-pant moron with his hat on sideways, high on dope or half drunk, running into the back of your A. These idiots are everywhere! .... even on the interstate and many are not kids either.

Competing with modern traffic speeds is one of the reasons why the A is so appealing to so many. If your A is not up to par then fix it or upgrade it so it will be. OR, stay on the milk-route with your eye glued to the rearview mirror instead of watching for the possible cows, dogs, cats, deer, skunks, armadillos (TX), 'possums, people, etc. that are often in or run across these roads. Of course since you're driving so slow maybe you can stop..... as long as there are no morons following too close behind you.

Just my opinion.

Larry B.

[MrTube]

Originally Posted by Larry Brumfield

Moreover, even on the so called milk-route you run the risk of some baggy-pant moron with his hat on sideways, high on dope or half drunk, running into the back of your A. These idiots are everywhere! .... even on the interstate and many are not kids either.

You forgot to mention they typically drive reclined in the seat so they can barely see over the wheel and sit leaned over towards the middle of the car, don't really know whats going on and they like it that way.

[Larry Brumfield]

Originally Posted by MrTube

You forgot to mention they typically drive reclined in the seat so they can barely see over the wheel and sit leaned over towards the middle of the car, don't really know whats going on and they like it that way.

Mr. Tube, that's called "diggin' the scene with the gangster lean"

It is only appealing to other morons and low-lifes with like mind.

Larry B.

[Cool Hand Lurker]

Mr. Tube, that's called "diggin' the scene with the gangster lean"

It is only appealing to other morons and low-lifes with like mind.

Larry B.

Back in the late '50s we called that "riding slick" on the North Side of Minneapolis!

[skip]

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When driving too slow, the closing rate is a killer. Watch the movie LeManns for an excellent discussion about running fast cars and slow cars at the same time on the track...

skip.

[Bill Steiner]

I would not run it that way. Bill

[George Miller]

If you ran a new car for long periods of time wide open it would not last.

[Kohnke Rebabbitting]

Originally Posted by Larry Brumfield

As mentioned in my post above, even Henry Ford implied that one should not run the Model A wide open, i.e., 65 miles an hour as in road tests.

Now do any of you think that Henry Ford himself would have made a statement about comfortable driving at 50 to 60 miles an hour if the Model A was going to throw rods or come apart? ....

Naturally, if your Model A has thicker babbitt and a crankshaft ground down so many times it's about like a toothpick, OR high mileage with shims removed OR unknown condition of bearings from a lot of use, it's best to putt putt 45 in your Model A.

BUT, as it was when Henry made it, the Model A was made to run! Wouldn't Ford have lost his credibility if the Model A engines had come all apart shortly after purchase.... "Sorry, you shouldn't have gone over 45."

The crankshaft whipping and worn out center main didn't happen overnight either. People drove them for miles with no problems.

All this reminds me of a statement a friend made to me 31 years ago when I first got into Model A's. My friend, who was a grown man when the Model A was new and a mechanical engineer, said that if the men alive back then could come back and watch how many of the Model A'ers drive today, they'd laugh!


Larry B.

Larry, question for you? What does thick babbitt have to do with any thing, other then some what more expense. Herm

[Kohnke Rebabbitting]

Originally Posted by Larry Brumfield

As mentioned in my post above, even Henry Ford implied that one should not run the Model A wide open, i.e., 65 miles an hour as in road tests.

Now do any of you think that Henry Ford himself would have made a statement about comfortable driving at 50 to 60 miles an hour if the Model A was going to throw rods or come apart? ....

Naturally, if your Model A has thicker babbitt and a crankshaft ground down so many times it's about like a toothpick, OR high mileage with shims removed OR unknown condition of bearings from a lot of use, it's best to putt putt 45 in your Model A.

BUT, as it was when Henry made it, the Model A was made to run! Wouldn't Ford have lost his credibility if the Model A engines had come all apart shortly after purchase.... "Sorry, you shouldn't have gone over 45."

The crankshaft whipping and worn out center main didn't happen overnight either. People drove them for miles with no problems.

All this reminds me of a statement a friend made to me 31 years ago when I first got into Model A's. My friend, who was a grown man when the Model A was new and a mechanical engineer, said that if the men alive back then could come back and watch how many of the Model A'ers drive today, they'd laugh!


Larry B.

Originally Posted by Kevin in NJ

Depends

A factory engine was carefully balanced and would go over 60 mph. So an engine brought back to factory specs should have little troubles.

Babbitt is a bearing that let's the crank spin. The enemy of Babbitt are conditions that let the Babbitt be pounded. Out of balance and lugging are the two conditions you need to avoid. Running high rpms with a balance system is a good condition.

Finding a properly balanced engine today is another story. Many A's are not well balanced and will beat themselves up at high rpm.

Kev, what are you using for evidence that a Model A was Carefully Balanced at the factory. thanks Herm.

[Kohnke Rebabbitting]

Originally Posted by skip

I don't worry about the churn coming apart wide open as much as the two blade fan coming apart and going through something. Having said that...

" I Drive As If I Had A Raw Egg Between My Foot And The Accelerator Pedal. "

Nothing kills an engine more than rpm changes. Slow and steady. Baby her. Double clutch and wait for things in the transmixer to slow down or catch up. A blip on the throttle for up sifts and smooth as silk engagements .

My self imposed limit on speed is 45 mph. Fast enough. I did go to 53 mph once just for poops and grins.


skip.

Skip, your statement that nothing kills an engine more than R.P.M. changes is VERY true. One of the hardest things on a set of rods, other than NO OIL, is high R.P.M. shifts, even with out your double clutch especially. When the rods free float, not pushing or pulling, at high R.P.M. shifts, you are taking a big chance. Thanks Herm.

[MrTube]

Originally Posted by George Miller

If you ran a new car for long periods of time wide open it would not last.

A new car is not a low compression 4:1 40HP 200cubic inch cast iron engine that runs around 2200-2800rpm wide open. A modern engine producing 100+HP per liter running 11:1 compression with boost and redlining at 6500K is an entirely different beast

Not really comparing oranges to oranges. The closest thing I would compare a model A engine to (please forgive me Ford Barn) Is a lawn mower engine, which run fine at 3000rpm 24\7 without pressurized oil systems and without special bearings.

[Larry Brumfield]

Originally Posted by Kohnke Rebabbitting

Larry, question for you? What does thick babbitt have to do with any thing, other then some what more expense. Herm

Thicker babbitt is more apt to compress excessively under load.Larry B.

[Kohnke Rebabbitting]

Originally Posted by Larry Brumfield

Thicker babbitt is more apt to compress excessively under load.Larry B.

Another question Larry, did you get your vast knowledge of thick babbitt failing from remanufacturing babbitt bearings in your rebabbitting business, 6 to 7 days a week, for the last 42 years, or are you just repeating some old timers opinions, that you heard at swap meets saying that thick babbitt won't ever work. I will guarantee if thick babbitt fails, it isn't from any thickness. If babbitt is compressing under load, you have a bearing that has way to much clearance, has nothing to do with thickness. The same to much clearance that would compress a thick wall bearing, will also compress a thin wall bearing at the same rate, and that is a fact Jack, or I mean Larry. Ok, lets hear it, thanks Herm.

[J Franklin]

I have heard that one weakness of thick babbit is the fact that it keeps heat from dissipating through the steel of the rod which is a better conductor of heat. Fact or fiction? I don't know.

[George Miller]

Re: Can you run an A wide open?
Quote:
Originally Posted by George Miller
If you ran a new car for long periods of time wide open it would not last.


A new car is not a low compression 4:1 40HP 200cubic inch cast iron engine that runs around 2200-2800rpm wide open. A modern engine producing 100+HP per liter running 11:1 compression with boost and redlining at 6500K is an entirely different beast

Not really comparing oranges to oranges. The closest thing I would compare a model A engine to (please forgive me Ford Barn) Is a lawn mower engine, which run fine at 3000rpm 24\7 without pressurized oil systems and without special bearings.


Of course I know all that. My point is you can not run any engine wide open for long periods of time. With new cars you could not run wide open in drive you would be going to fast for the roads. I got some experience also about 60 years of working on cars. No I do not pour babbitt, But I do inserts. I for one would not want thick babbitt.

[Special Coupe Frank]

I'm still waiting for someone to offer some suggestions as to WHERE there was enough good highway in 1928-31 to run ANY car at 60 MPH for more than a sprint of a mile or two ? ( The nevada salt flats ? )

I don't think the average new A-buyer had enough good road to "call" Old Henry's bet that the Ford would run 60-65 mph, unless they put it on a race track... I think Old Henry made a safe, calculated marketing bet. And I'll bet he wouldn't have made the claim unless he felt confident that his product had the Moxie; but I don't think he was thinking about his New Ford running 60 MPH for hours on end.

I have a book published by the Ford Technical School around 1940 on shop tehnique, and from that and what else I've read about Old Henry, I have no doubt that Ford's manufacturing tolerances / engineering were probably second to none... a properly run-in, factory-fresh Model A probably stood the best chances for surviving sustained high-speed running, no disrespect intended towards the rebuilders who gather here.

My caution would be more aimed at folks who try to push an old jalopy that hard...


Regards,

SC Frank

[Patrick L.]

Yep, from everything I've been able to find out, the '60 mph deal' was used as a sales gimmick to show customers that the car would go 60 mph as the higher priced cars would.. Where in 1931 could one drive that fast? I enjoyed looking at the recent articles that Skip posted ;; 60 mph = 3000 rpm.. Most engines of this era were under-square which means low rpm and high piston speeds.. Personally, I'll keep to a reasonable 'Model A' speed and see if I can't get many more years out of the 1961 engine rebuild .. I won't even mention the vehicles safety issues and stopping distances..

[Tom Foster]

Originally Posted by George Miller

Re: Can you run an A wide open?
Quote:
Originally Posted by George Miller
If you ran a new car for long periods of time wide open it would not last.

Of course I know all that. My point is you can not run any engine wide open for long periods of time.

When I was a Young Sprout 50+ years ago my high school science club went to Southwest Research Institutie in San Antonio and we were treated to a visit to the engine shop where they were testing lubrication systems. One current-model V8, don't know the make, had been running full throttle, 6,000rpm, for 38 days continuously.
I'm afraid you made an inoperative statment, Mr. Miller.
Fearless

[MrTube]

Originally Posted by Tom Foster

When I was a Young Sprout 50+ years ago my high school science club went to Southwest Research Institutie in San Antonio and we were treated to a visit to the engine shop where they were testing lubrication systems. One current-model V8, don't know the make, had been running full throttle, 6,000rpm, for 38 days continuously.
I'm afraid you made an inoperative statment, Mr. Miller.
Fearless

The Duesenberg straight 8 used in the 20's and 30's model J was able to rev above 4K with no problem as well. Of course theres really no comparison between the ford model A engine and a Duesy engine but they are the same era.

[Kohnke Rebabbitting]

Originally Posted by J Franklin

I have heard that one weakness of thick babbit is the fact that it keeps heat from dissipating through the steel of the rod which is a better conductor of heat. Fact or fiction? I don't know.

Heat conductivity is the same on a thin piece of babbitt, as it is on a thick wall piece of babbitt. A thick, or thin piece of brass will get hot fast when you grind on it, the thick one just takes a minute longer. Now the place where you loose heat transfer is where the babbitt meets the bearing shell. Cast iron has to be CORRECTLY peened, and steel CORRECTLY tinned, BUT the babbitt has to be stuck to the tinning, in which many places putting out bearings, are not. The OIL behind the bearing is what cuts down heat transfer, as OIL is not a good conductor, not the thickness of the babbitt, or the thickness of the shell. you need babbitt metal, to shell metal contact ((( 100%))), on a tinned, or peened bearing, or it will fail before its time. Just because you tin a bearing shell, that does NOT mean it stuck, when it cooled. If it didn't, the babbitt will push in, and out to the shell, and bust up, that also goes for cast iron pouring. feed back anyone, thanks Herm

[Kevin in NJ]

Balancing was specified on the crank print and heavily touted in the book "Know Your Model A Ford" and in the dealer sales literature recent published in the 'Restorer'.

I do not have the crank print handy, but I believe 1/4oz dynamically was the limit.

The rod print specs a specific weight +-1 gram on each end.

I have heard the pistons were supposed to be done down to a few grams each, but I do not have documentation.

The flywheel was balanced, but I am not 100% if it was done dynamically.

One other tid bit. I was reading something where they were explaining the machine that balanced the cranks and how accurate the machine could be. It could balance the crank better than Fords spec.

An interesting aside. My brother was taking down a flywheel and found a fairly large void in the casting. Opposite the void was a fairly large balance hole drilled into the edge.

[George Miller]

Originally Posted by George Miller
Re: Can you run an A wide open?
Quote:
Originally Posted by George Miller
If you ran a new car for long periods of time wide open it would not last.

Of course I know all that. My point is you can not run any engine wide open for long periods of time.

Tom I would have to see that to believe it. just because it is written does not make it true.
If engine could run wide open for ever, how come NASCAR engines have to be rebuilt after ever race.

[V4F]

i ran mine out yesterday . about 75 mph , but its the first & only time ill do it . not comfortable for me or my car at that speed ................ me & my car love 55-60 mph . ....... steve

[Patrick L.]

Herm , I'm not a babbitt guy, never did it.. But, I've installed my share of inserts and one of my pet peeves is to watch someone dunk the shell/insert into a puddle of oil and stick it in the block/rod/cap..That drives me nutz.. Regardless, a bearing is a bearing isn't it..

[Kohnke Rebabbitting]

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Originally Posted by Patrick L.

Herm , I'm not a babbitt guy, never did it.. But, I've installed my share of inserts and one of my pet peeves is to watch someone dunk the shell/insert into a puddle of oil and stick it in the block/rod/cap..That drives me nutz.. Regardless, a bearing is a bearing isn't it..

Yup, your right Patrick, sure don't need any oil behind any bearing. Babbitt, or modern insert, if they hold up, there good to go. thanks Herm.

[Kohnke Rebabbitting]

Originally Posted by Kevin in NJ

Balancing was specified on the crank print and heavily touted in the book "Know Your Model A Ford" and in the dealer sales literature recent published in the 'Restorer'.

I do not have the crank print handy, but I believe 1/4oz dynamically was the limit.

The rod print specs a specific weight +-1 gram on each end.

I have heard the pistons were supposed to be done down to a few grams each, but I do not have documentation.

The flywheel was balanced, but I am not 100% if it was done dynamically.

One other tid bit. I was reading something where they were explaining the machine that balanced the cranks and how accurate the machine could be. It could balance the crank better than Fords spec.

An interesting aside. My brother was taking down a flywheel and found a fairly large void in the casting. Opposite the void was a fairly large balance hole drilled into the edge.

Kev, the only reason I asked, is with the A's we have rebuilt, and all the spun rod sets we sold, and balanced in sets, and we started with a set that each rod was the same weight, as we would do about 500 each time to a batch. I never found any thing to make me think that any of the rods were balanced, they had no metal removal marks, and they were along ways off, for 0 balance. The cranks are drilled, but not zeroed. The flywheels, the same thing here, cut down about 100??? flywheels, I'am guessing about 30?? had casting flaws. But rebalance, and grind and all is well. The flywheels that we balanced in the past, alot were 12, to 23 grams out. thanks Kev, Herm.

[MrTube]

Kohnke Rebabbitting. I may have missed it if you said it but, In your opinion is it fine to run the A engine wide open at 2800-3K rpms or not?

I assume it will shorten the engines life (as with ANY engine) but I doubt it would do any real harm assuming everything is in proper working order?


In regards to sudden RPM changes damaging engines, We used to have a family friend who loved to rev his engines constantly. He felt it impressed people. At any rate, on one of engines the timing chain jumped a tooth with only 30,000 miles on it. It was always assumed the extreme wear on the chain was from him constantly reving the engine, forcing it to suddenly speed up and slow down the cam. This was on a 1960s chevy smallblock (327 I think) my dad had built for him.

[stautz]

50,000 miles on a Model A is like 150,000 miles, maybe 200,000 miles, on a car today. I drive with my foot on the floor most of the time because its more fun and I'm sure that's how the kids drove their parents' Model A.

[Larry Brumfield]

Originally Posted by Kohnke Rebabbitting

Another question Larry, did you get your vast knowledge of thick babbitt failing from remanufacturing babbitt bearings in your rebabbitting business, 6 to 7 days a week, for the last 42 years, or are you just repeating some old timers opinions, that you heard at swap meets saying that thick babbitt won't ever work. I will guarantee if thick babbitt fails, it isn't from any thickness. If babbitt is compressing under load, you have a bearing that has way to much clearance, has nothing to do with thickness. The same to much clearance that would compress a thick wall bearing, will also compress a thin wall bearing at the same rate, and that is a fact Jack, or I mean Larry. Ok, lets hear it, thanks Herm.

Sorry Jack ..... or is it Gomer? .... I mean Herm.... I disagree with your view on thick babbitt.

Also, that 42 year comment doesn't necessarily impress anybody. On the other hand, if your knowledge of babbitt bearings has been increasing DAILY for 42 years then you must be a smart s.o.b........ More than likely though you learned most of what you know in about 5 years or so ... so that means you have only 5 years experience 8.4 TIMES OVER!

In my opinion, the thinner the babbitt the stronger. Now depending on the differences it may not be greatly significant in all cases or even be a problem but it's still there. If an undersized crank is off center a bit too much or slightly distorted in its operation for one reason or another; like so many of them are; the crank will tend to beat and compress the thicker soft babbitt more than the thinner by comparison and create excessive clearance possibly leading to bearing failure.

Of course if a bearing fails you can bet that it won't be the fault of the engine rebuilder!

Just my experience ..... stated in the same manner as you.


Larry B.

[29RPU]

Man, this is awesome. Not only did a thread I start gain so much popularity, zig-zag a bit off topic, AND get some great opinions about running an A wide open, but there are little verbal scuffles going on in here as well! Who could ask for anything more. All we need now is some virtual beer. Thanks guys!

[MrTube]

Originally Posted by 29RPU

Man, this is awesome. Not only did a thread I start gain so much popularity, zig-zag a bit off topic, AND get some great opinions about running an A wide open, but there are little verbal scuffles going on in here as well! Who could ask for anything more. All we need now is some virtual beer. Thanks guys!

Yea... Look what you did.. mom always said not to play ball in the house...

The only opinion I have on thick babbit is, obviously there were things considered in designing the engine and they for SOME odd reason picked the original thickness and I would have to assume deviating from this thickness in any direction could and most likely would cause problems. Again, this is just going on my usual assumption that all things are done for a reason (and they usually are).

[Pete]

"In my opinion, the thinner the babbitt the stronger and the thicker the softer. Now depending on the differences it may not be greatly significant in all cases or even be a problem but it's still there." (Larry Brumfield)

I just happened across this thread so I guess I missed most of the fun.
Larry is right according to the laws of physics..That is one reason modern shell bearings only have babbit .0002 thick.
Actually a given bearing material will deflect at the same RATE for different thicknesses but the thicker one will deflect farther with the same load thus causing more movement in the total assembly..This movement caused by the reciprocating forces equates to less bearing life.
The bearings in a model A engine are so lightly loaded that almost any thickness would work though.

[Marco Tahtaras]

Originally Posted by Kohnke Rebabbitting

Kev, the only reason I asked, is with the A's we have rebuilt, and all the spun rod sets we sold, and balanced in sets, and we started with a set that each rod was the same weight, as we would do about 500 each time to a batch. I never found any thing to make me think that any of the rods were balanced, they had no metal removal marks, and they were along ways off, for 0 balance. The cranks are drilled, but not zeroed. The flywheels, the same thing here, cut down about 100??? flywheels, I'am guessing about 30?? had casting flaws. But rebalance, and grind and all is well. The flywheels that we balanced in the past, alot were 12, to 23 grams out. thanks Kev, Herm.

Hi Herm,

You were looking in the wrong place based on modern methods. Note the circumferential grind marks on the edges of both ends of the connecting rod. This was the last stage and when you study original rods you will find no two identical. The amount of "meat" removed is based on the particular weight removal requirements. I'd love to see the original machine. The machine certainly must have been automatic like the piston balancing machine which weighed the shavings and quit when the shavings weighed the same amount as the determined excessive weight.

At the beginning of production Ford balanced connecting rods in sets of four. They made it very clear to the dealers that they MUST replace connecting rods in complete sets to maintain the proper balance. Ford worked out their production / balancing methods and began making ALL connecting rods the same weight beginning April 24, 1928. They began providing the same for service May 10, 1928.

[Kevin in NJ]

Here are the crank specs off the drawing.

[Kurt in NJ]

Herm, I think that the method used to balance the rods is the machining on the outside of both the big end, and the small end, they all seem to be very close to the same at the edge, but the depth, and the angle is somewhat different, with the thicker forgings having more machining ---the same method was carried over to the V8 flathead rods.

The Ford blueprint shows a weight spec of 198 grams +-1 for the small end, and 512 +- 1 for the big end.

I had a boxed NOS set of B rods, they weighed out within 1/2 gram of each other at both ends.

The crankshaft print has a balance spec--"shaft must be in balance dynamically within 3oz inch at any 1 point of reference, shaft must be in balance statically within 3 oz inch"

[Bob Johnson]

Here are two rods from the same engine. Notice the difference in the amount of material that has been removed at each end.

Bob

[Kohnke Rebabbitting]

Originally Posted by Larry Brumfield

Sorry Jack ..... or is it Gomer? .... I mean Herm.... I disagree with your view on thick babbitt.

Also, that 42 year comment doesn't necessarily impress anybody. On the other hand, if your knowledge of babbitt bearings has been increasing DAILY for 42 years then you must be a smart s.o.b........ More than likely though you learned most of what you know in about 5 years or so ... so that means you have only 5 years experience 8.4 TIMES OVER!

In my opinion, the thinner the babbitt the stronger. Now depending on the differences it may not be greatly significant in all cases or even be a problem but it's still there. If an undersized crank is off center a bit too much or slightly distorted in its operation for one reason or another; like so many of them are; the crank will tend to beat and compress the thicker soft babbitt more than the thinner by comparison and create excessive clearance possibly leading to bearing failure.

Of course if a bearing fails you can bet that it won't be the fault of the engine rebuilder!

Just my experience ..... stated in the same manner as you.


Larry B.

Yo, Larry, I am sorry the 42 year comment didn't do anything for you, you'll be glad to know I tried it on my girl friend this afternoon, and it didn't do anything for her either, so I went down my list of known workable things, and found one she did like. I was going to thank you for the smart S.O.B. comment, but after I reread it a couple of times, I realized that you probably forgot a word in that sentence. You are wrong about learning what I know in 5 years, it was more like two years, I was lucky to have a Clawson & Bals babbitt trouble shooter teach me, and he sold me all Clawson & Bals machines, that he was going to use, but didn't get to after his retirement, from then on the learning part is mostly being able to tell when a pour is good, as every bearing pours different, temperature, to fast, to slow, cool to fast, not fast enough ect. In your opinion Larry the thinner the babbitt the better, and that is just what it is, Your Opinion, has nothing to do with Reality. If we were not to rebuild thick babbitt bearings, 60% of the bearings we do would never let there engine run again. Most of the cars, tractors, and machinery from 1900 to into the 1920's were real thick babbitt, and or thick babbitted shells. the big old tractors, some of them 3/8, to 1/2 inch babbitt thickness in rods and mains, and they are no better or worse than the model A. When babbitt thickness is cut, in factory engine building, it was mostly done to save money. 216's Chevy rods, from 1937 to 1953, have about .010 wall thickness of babbitt, and that works just fine, as they were all done at the Chevy factory, or a place they farmed them out to. The problem with rebuilding them the first time, is that you can't hit the same hole, as it were. So the 216's are bored to 100 thousands over standard bore with out babbitt. so there goes your thick babbitt that won't work again, BUT IT DOES. The babbitt wall now is .060 thousands thick instead of .010 thousands in a factory untouched rod. So Larry, in 42 years, and NO bad bearings EVER, in your experience what am I doing wrong. As far as an engine rebuilder ever being at fault, we stand behind every bearing we do. Babbitt bearing are just like insert bearings, in that if you have a bearing blow, weather babbitt, or insert you normally can tell why, just like an insert book, that has many pictures showing inserts, and there cause of failure. As far as an engine rebuilder never being at fault, the owner has to take some of the fault, as if his wife is a real you now what, just remember he picked her. Thanks Larry Jack, Gomer.

[Kohnke Rebabbitting]

Originally Posted by MrTube

Kohnke Rebabbitting. I may have missed it if you said it but, In your opinion is it fine to run the A engine wide open at 2800-3K rpms or not?

I assume it will shorten the engines life (as with ANY engine) but I doubt it would do any real harm assuming everything is in proper working order?


In regards to sudden RPM changes damaging engines, We used to have a family friend who loved to rev his engines constantly. He felt it impressed people. At any rate, on one of engines the timing chain jumped a tooth with only 30,000 miles on it. It was always assumed the extreme wear on the chain was from him constantly reving the engine, forcing it to suddenly speed up and slow down the cam. This was on a 1960s chevy smallblock (327 I think) my dad had built for him.

Mr. Tube, I guess I wouldn't want to say much about wide open,VS not, I think what I would do if I had an A yet, is put in an overdrive, and keep the R.P.M's down to a 45 stock speed, they have plenty of power to handle it. thanks Herm.

[Kohnke Rebabbitting]

Originally Posted by Kurt in NJ

Herm, I think that the method used to balance the rods is the machining on the outside of both the big end, and the small end, they all seem to be very close to the same at the edge, but the depth, and the angle is somewhat different, with the thicker forgings having more machining ---the same method was carried over to the V8 flathead rods.

The Ford blueprint shows a weight spec of 198 grams +-1 for the small end, and 512 +- 1 for the big end.

I had a boxed NOS set of B rods, they weighed out within 1/2 gram of each other at both ends.

The crankshaft print has a balance spec--"shaft must be in balance dynamically within 3oz inch at any 1 point of reference, shaft must be in balance statically within 3 oz inch"

Kurt, I have had many sets of used rods , the owners said were original to there car, but you know how that goes. I know about the machining on both ends of the rods, but never fully under stood the purpose, as when we would get in so called sets to spin for a balance set, I would put them on the balancer, and have never found a balanced set. That was with used babbitt, no babbitt, and or new machined babbitt. When we spun 500 rods, pre machine to .060 under, weigh all 500, lay them in long lines, and pick them for total weight. now you have many sets that each rod weighs the same, if they were balanced that close at the factory, why were they such a long ways off when you went to balance them. I don't know. They all had the same weight of shims, and rod nuts. The Model B rods, we only had about 250 cores, and we got good sets out of fewer rods, but they were closer to balance. The Model T rods were the pits to balance. Thanks Herm

[Kohnke Rebabbitting]

Originally Posted by Marco Tahtaras

Hi Herm,

You were looking in the wrong place based on modern methods. Note the circumferential grind marks on the edges of both ends of the connecting rod. This was the last stage and when you study original rods you will find no two identical. The amount of "meat" removed is based on the particular weight removal requirements. I'd love to see the original machine. The machine certainly must have been automatic like the piston balancing machine which weighed the shavings and quit when the shavings weighed the same amount as the determined excessive weight.

At the beginning of production Ford balanced connecting rods in sets of four. They made it very clear to the dealers that they MUST replace connecting rods in complete sets to maintain the proper balance. Ford worked out their production / balancing methods and began making ALL connecting rods the same weight beginning April 24, 1928. They began providing the same for service May 10, 1928.

Marco, the message I left Kev, explains why I never seen to much balance in the Model A rods. I guess the thing I would ask you is who did your rebuilt rods, did they still have there right box. I have seen several rods like that, but never a shipping box. thanks Herm.

[Barry in St.Paul]

Originally Posted by steve norcal

i ran mine out yesterday . about 75 mph , but its the first & only time ill do it . not comfortable for me or my car at that speed ................ me & my car love 55-60 mph . ....... steve

Steve, I'm curious what carb you are using? I have a high-speed (3.54) rear-end, Brumfield 5.9 head and touring cam, and "wide open" on flat road I seem to top out at about 60-65mph. But, it seems it is simply the limit of my Zenith carb. Wondering if you are using a Zenith or a Tilly? I don't care to drive any faster than I can go now, just curious :- )
thanks!

[Ryan]

I deleted some posts here fellas... I just have a low tolerance level for drama...

Carry on... without the name calling of course.

[Larry Brumfield]

Originally Posted by Kohnke Rebabbitting

Yo, Larry, I am sorry the 42 year comment didn't do anything for you, you'll be glad to know I tried it on my girl friend this afternoon, and it didn't do anything for her either, so I went down my list of known workable things, and found one she did like. I was going to thank you for the smart S.O.B. comment, but after I reread it a couple of times, I realized that you probably forgot a word in that sentence. You are wrong about learning what I know in 5 years, it was more like two years, I was lucky to have a Clawson & Bals babbitt trouble shooter teach me, and he sold me all Clawson & Bals machines, that he was going to use, but didn't get to after his retirement, from then on the learning part is mostly being able to tell when a pour is good, as every bearing pours different, temperature, to fast, to slow, cool to fast, not fast enough ect. In your opinion Larry the thinner the babbitt the better, and that is just what it is, Your Opinion, has nothing to do with Reality. If we were not to rebuild thick babbitt bearings, 60% of the bearings we do would never let there engine run again. Most of the cars, tractors, and machinery from 1900 to into the 1920's were real thick babbitt, and or thick babbitted shells. the big old tractors, some of them 3/8, to 1/2 inch babbitt thickness in rods and mains, and they are no better or worse than the model A. When babbitt thickness is cut, in factory engine building, it was mostly done to save money. 216's Chevy rods, from 1937 to 1953, have about .010 wall thickness of babbitt, and that works just fine, as they were all done at the Chevy factory, or a place they farmed them out to. The problem with rebuilding them the first time, is that you can't hit the same hole, as it were. So the 216's are bored to 100 thousands over standard bore with out babbitt. so there goes your thick babbitt that won't work again, BUT IT DOES. The babbitt wall now is .060 thousands thick instead of .010 thousands in a factory untouched rod. So Larry, in 42 years, and NO bad bearings EVER, in your experience what am I doing wrong. As far as an engine rebuilder ever being at fault, we stand behind every bearing we do. Babbitt bearing are just like insert bearings, in that if you have a bearing blow, weather babbitt, or insert you normally can tell why, just like an insert book, that has many pictures showing inserts, and there cause of failure. As far as an engine rebuilder never being at fault, the owner has to take some of the fault, as if his wife is a real you now what, just remember he picked her. Thanks Larry Jack, Gomer.

Ryan, allow me to tone things down a bit. The following needs to be said:

I never said that thick babbitt would not work ... and at the same time my other comments about babbitt are the exact truth!

Take the time to reread my posts and look for the words "apt", "possibly" and "IF the crank was off center a little bit or distorted in its operation for one reason or another."

You will see that I did not say that thick babbitt would fail on the average Model A out there on the street. If one were driven at a reasonable speed and load it would run just fine with thick babbitt UNLESS it had the problems that I alluded to in my posts. And if you'll reread everything you will see that I didn't say that bearing failure was a done deal even with the problems, I said "possibly."

Out on the dirt track using a Model A engine (in a different type car) I've had problems with toothpick cranks and thick babbitt.

I also don't believe there's never been a bad bearing in 42 years ..... he just never heard about it, that's all. Some people won't report anything and others will report the slightest problem.

For yet another man's experience instead of mine, go to and read what a renown automotive engineer knows about thick babbitt and the Model A. Click on the link below and then scroll down to where it says NOS Cap Showing Original Babbitt Thickness.

http://idisk.mac.com/forever4/Public...aringshims.htm


Larry B.

[Kohnke Rebabbitting]

Originally Posted by Larry Brumfield

Ryan, allow me to tone things down a bit. The following needs to be said:

I never said that thick babbitt would not work ... and at the same time my other comments about babbitt are the exact truth!

I also don't believe there's never been a bad bearing in 42 years ..... he just never heard about it, that's all. Some people won't report anything while others will report the slightest problem.

Kohnke is not the only person with engine experience.


Larry B.

Ryan, allow me to tone things down a bit. The following needs to be said END QUOTE) Dear, Dear Lar. I do so love the way you have of toning things down, you are SUCH a card.

(QUOTE) I never said that thick babbitt would not work ... and at the same time my other comments about babbitt are the exact truth! (END QUOTE) Lar, Lar, that is your truth, has nothing to do with Reality. There are many people like that, that Misdiagnosis a failure. IT IS ALWAYS, to much clearance, THAT WILL HAMMER IT OUT OR, NOT enough clearance that smears the babbitt, and then when the babbitt gets hard again, "IF IT COOLS" all the little smear granular pieces break off, and go back through the bearing again, and eat it up. Bad installation of the babbitt, that is the biggest fault of bearing failure, " If everything else is right" THERE HAS NEVER BEEN A BABBITT BEARING IN THIS WORLD FAIL BECAUSE OF THICKNESS. All REASONS that take out modern insert bearings, take out babbitt, except modern inserts can spin, an babbitt will break apart when it lets go of its backing, tinned, or peened. When a bearing fails, IT DOESN'T know if is thick or thin. If the bad bearing hasn't run to long, and destroyed all the evidence, you can tell on the shell what has happened to adhesion.

(QUOTE)I also don't believe there's never been a bad bearing in 42 years ..... he just never heard about it, that's all. Some people won't report anything while others will report the slightest problem.(END QUOTE)

Now, my dear Lar, I can't in all honesty say I can fault you for not believing I haven't had a bad bearing in 42 years, I have heard the guys on the Barn talk about alot of real bad experiences, which is always of Great interest to me. You say some people won't report, I AGREE with that 100%. I think that happens, more then not. The one thing you don't know about my shop, is that for at least 32 years, I had a 6 man shop, "until they started retiring,"counting me, yes, I counted myself. In short, to find a good replacement, just don't work out, spend 6 months training a Guy, and when they can do some things on there own, the next day they come in and say, they will moving closer to ther girl friend in collage. I couldn't blame them, but I think they knew that was a possibility. Anyway Lar, I don't think you can imagine how big a pile of bearings that might be in 42 years. Now 99% of our bearings are rebuilt for other engine rebuilders, and machine shops, always have been. Believe you me Lar, if one of our bearings went bad in there engines, I WOULD HERE FROM THEM, THEY WOULD NOT LET YOU GET BUY WITHOUT THAT, as their customer would be on them to fix it. There would be no money in it for the engine builder, or me, we do stand behind what we make, but even at that, I bet that would be the last time he used us, so thats why we try to build them to last, weather spun, or Jig poured. We sold Spun Model T rods, cam bearings, and ball caps, Model A rods, and Model B rods, to most of the major parts houses, until the rebuilding cost had a to large of margin between, our spun rods, and jig poured rods, so we don't do them anymore, except for our own engines.

(QUOTE)Kohnke is not the only person with engine experience. END QUOTE) Yes, Mr. Lar, I agree with that a 100%, in fact, of all the guys that are on the barn, that are engine builders, I am probably in THE BOTTOM 10% but it will never be about thick babbitt. Now, I shouldn't have to come back here again, unless Ryan really hurts me bad or you use one of your ALLOW ME TO TONE THINGS A BIT STATEMENTS.

I am going to TRY to post some pictures of a set of 1926 CHEVY 4 rods, for a shop in New York State. They are .060 under size, way to thick of babbitt. Love Ya Lar, Herm.

[30Tudor]

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Larry and Herm - I really respect what both of you guys have to say and I think its OK that you have differences in opinions. However, getting personal just takes away from the whole spirit of this place which I believe is a forum for sharing ideas and learning from each other. I'm just worried that you guys are going to end up in a fight to the death and then unfortunately the rest of us will be deprived of your excellent contributions in the future.

[Larry Brumfield]

Originally Posted by 30Tudor

Larry and Herm - I really respect what both of you guys have to say and I think its OK that you have differences in opinions. However, getting personal just takes away from the whole spirit of this place which I believe is a forum for sharing ideas and learning from each other. I'm just worried that you guys are going to end up in a fight to the death and then unfortunately the rest of us will be deprived of your excellent contributions in the future.

Thanks for your concern but neither one of us is as excited as it may appear.

Larry B.

[PC/SR]

Herm: Not to distract from the debate, which I follow with interest, I am impressed that the oil grooves in the Chev rods are really similiar to the MOdel A rod grooves. Were they that way stock, or is that cut a later improvement? Also note two spurt holes in the big end. Was there a dipper arrangement? It looks like there may be a hole in the cap next to the center protrusion down from the cap and was that a "dipper?" I can't really tell from the photos. I wonder that if the Chev and Ford engineers came up with basically the same groove design it may be the best design, and improper grooving on rebuilds may be a cause of failure. Thanks Pat

[Kohnke Rebabbitting]

Originally Posted by PC/SR

Herm: Not to distract from the debate, which I follow with interest, I am impressed that the oil grooves in the Chev rods are really similiar to the MOdel A rod grooves. Were they that way stock, or is that cut a later improvement? Also note two spurt holes in the big end. Was there a dipper arrangement? It looks like there may be a hole in the cap next to the center protrusion down from the cap and was that a "dipper?" I can't really tell from the photos. I wonder that if the Chev and Ford engineers came up with basically the same groove design it may be the best design, and improper grooving on rebuilds may be a cause of failure. Thanks Pat

Yo Pat, the Chevy rods didn't start putting in X groves, untill the the first Chevy 6 cylinder in 1929. All of the Chevy 4 Cylinders were smooth inside. The holes that were drilled in the web of the rod, on both sides, were just about 3/8 between holes, and FORD drilled their web holes to intersect in to the same hole. Now on the rods I posted, there is a oil hole in the cap that has, like you said, a protrusion, or, for lack of a better word "dipper" in front of it, that when it hits the oil, it splashs it in the hole, I Hope, although it is not a REAL dipper in the metal on the cap. There were many makes that had that design. I put in the X groves in all rods that didn't have groves, if the rod is made like that, as there is no design better, as 1929 Chevys had them with tin dippers clear up to 1953 in the 216 Chevy sixs, although the 216's have a different oil well, and oil grove design. I will post a picture of our spun poured Model T rods, that we used to build, like Model A's. Thanks Pat, Herm.

[Mike V. Florida]

How to you pour babbitt and play the banjo at the same time?

[James Rogers]

Originally Posted by PC/SR

Herm: Not to distract from the debate, which I follow with interest, I am impressed that the oil grooves in the Chev rods are really similiar to the MOdel A rod grooves. Were they that way stock, or is that cut a later improvement? Also note two spurt holes in the big end. Was there a dipper arrangement? It looks like there may be a hole in the cap next to the center protrusion down from the cap and was that a "dipper?" I can't really tell from the photos. I wonder that if the Chev and Ford engineers came up with basically the same groove design it may be the best design, and improper grooving on rebuilds may be a cause of failure. Thanks Pat

Pat, I just finished a 28 Chevy rebuild and the stock rods were not grooved. The rods were smooth with only holes to allow oil migration and were only worn enough to need reconditioned. The dipper on the cap is solid and was for splash ing oil but has a hole slightly in front of it. The Chev engine has 4 small oiler tubes directed from the oil pump to spray oil directly at the holes in the rod caps. It must work since the miles were high on this car and wear was low but it still needed rebuilt.

[Kohnke Rebabbitting]

Originally Posted by Mike V. Florida

How to you pour babbitt and play the banjo at the same time?

A 5 string banjo only plays happy music, even when I play, and it makes you pour faster, and I have always been able to multitask. thanks Herm.

[PC/SR]

James and Herm: Thanks for the info. I had no idea Chevy had the oil spray tubes that early. They were in my Mother's 53 Chev, but I could never get #2rod right. The shims were long gone and I would file the cap but the knock would always come back, probably because by that time the cap was shaped more like a football than a circular bearing. One day the crankshaft broke right in two behind #2. Never heard of that before or since. Pops was not happy. Jim Brierely told me that he once saw an A (or maybe B) block with about a mile of tubing set up for tubes to spray oil directly at the dippers. Lots of work to do that and I doubt it would be much of an improvement except maybe at high speed when the dipper troughs might run out of oil but at that point a full pressure system would be the way to go.
PS to Mike V Florida: OK, I'll bite. HOw do you pour babbitt and play the banjo at the same time?

[George Miller]

I have a comment about thick babbitt. I'm not taking sides with and one, just what I think. My experience with thick babbitt is not good. It is inclined to pound out, flake, crack. Will it work for a stock engine running at 45 and under Probably. would it run as long as thin babbitt I do not think so. My experience as a mechanic and a full time machinist in the hydraulic business, I say it will not hold up as well.

[Dave in MN]

Good question 29RPU. Great activity on this thread.

I also think that keeping up with the traffic in the slow lane is safer than holding up traffic. I regularly run 60-65 in the slow lane if needed with my "A". I know from experience you need modifications to your engine, drive train and brakes to run at that speed for any extended period of time. A conventional engine will obtain that speed (60-70 mph) if you have adequate carburetion and proper advance on the dizzy. The problem is the engine won't last...the ability of the exhaust valves to handle the extreme heat from an extended high speed run is the problem I encountered with my stock engine. Burned up two exhaust valves thinking I could run at that speed.

After the experience with two burned exhaust valves I looked for ideas that would allow me to run at the high speeds but keep the engine together. When I rebuilt an engine for myself 9 years and 48,000 miles ago, I inserted the mains and rods, installed exhaust valve rotators, .125 over pistons (modern Chev 283 style...heaven forbid!), counterweighted the crank, lightened the flywheel and balanced and weighed everything. Installed a touring cam, Brumfield 5.9 head, electronic ignition, oversize intake valves, enlarged the intake manifold to "B" sizes. I run a standard performance tuned "A" Zenith carb. Installed the largest cooling capacity Brassworks pressurized radiator with an overflow tank I could fit in front of the fan. Changed to a V-8 pressure plate, added a Mitchell 26% overdrive to keep the rpms down, installed cast iron brake drums on all four. I have driven this engine and drive train hard for a lot of the 48,000 miles and have never had the pan off the engine. Replaced the head gasket twice in that many miles...once was just to check for carbon in the combustion chambers. If I have a head wind, I often have the pedal to the floor to keep up with the right lane on the freeway. I think my experience proves to me that these engine blocks can only handle the load demands of reaching the higher speeds if extensively modified and by holding the engine rpms down.

For what it's worth: Just once, I held the car steady at 70 to 72 mph for about 180 miles on an interstate with a small tail wind. (That was the speed those crazy Michigan people and matching crazy Minnesota guy were driving in the right lane on that day. I occasionally had to pass someone going slower...quite a few double take looks as I went by in my open air Phaeton...it was kind of funny to watch their looks of surprise. ) During this run, with the tail wind, the pedal was not to the floor so it probably can't be considered flat out wide open. I would have gone longer but I had to slow down and stop for gas.... The engine held together with the coolant temp staying just below 180 degrees.

Going fast is not for everybody...most say it defeats the purpose of owning a Model A...I agree. I like 25 to 45 mph best. Love the tours with our local Club...but we live 30 to 45 miles south of most of the starting points of the tours. Freeway travel is often our best option for part of our travel on tour day.

I.M.O. If you are going to go fast...know the limits of your car...Please keep a safe distance between you and the guy in front of you. If you reguarly drive in the right lane of the freeway, keep an ever watchful eye on the activity at the on and off ramps. People entering and exiting the freeway are probably your greatest danger.

Keep your brakes and steering tuned to the best they can be!
Good day!
Dave in MN

[George Miller]

Dave it sounds like you got it right.