Flathead highway speeds

[rickb9ol]

ive heard diffrent stories on how fast these flatheads will run.i would love to hear about others.mine is a 1935 ford pickup,rebuilt 37 flathead with aluminum heads and stromburg carb.37 three speed trans and 40 rear banjo.i do not know the rear ratio.here in texas speed limit is 70 mph and i can pass most people.impossible to read speedo as it bounces around too much..thanx everyone and keep on truckin

[Bruce Lancaster]

80 is in reach for many, some can go faster stock. Engine speed you want to run is probably the main limiter for most, within the range below arrest. Your likeliest rear ratios are 4.11 (engine really buzzing on the highway) and 3.78, fairly busy but not too high. Lube your speeedo cable!! If that doesn't do it' I can send you how to lube speedo bearing ideas.

Ford Service bulletins had a "Performance" road test section. This gave measurable standards for speed, acceleration, and economy, so if a customer complained that his car wass too thirsty or too slow, the dealer had a check to see if car was running to spec.
On the level road speed test, a '35-'37 85 should be able to hit in the 84-86 range to pass muster. A '40 Merc 239 with 3.54 standard seems to be the fastest of the period. It was expected to hit 95 flat.
My '48 could indicate 160KPH/100MPH, but who knows with what accuracy at the end of the speedo scale.

[Vic Piano]

We have several Flatheads ranging in years from ’39 to ’53 and we drive all of them locally and on the highway. Depending on the way the Flathead is set up, the rear gear ratio, the tire size, etc., each one performs differently and each one will find and let you know its “sweet spot” at highway speed. Remember that most of these cars and trucks were not built with driving on super highways in mind however, that does not imply that they can’t. This past weekend we drove our ’39 CD down to Long Boat Key from Odessa, FL (Just 100 miles each way), half of the trip on I-75 where the slower traffic does a steady 70mph. For the most part we kept up with the slower traffic, even passed a few. The car mellows out at between 65 and 70 mph with a stock 221 c.i. Flathead and 3.78 rear.

[Vic Piano]

that should have read '39 CS... the fat finger got me again.

[4dFord/SC]

I had to mount a magnetic placard on my 40's dash that reads, "CAUTION: Do Not Lower Windows at Speeds in Excess of 120 MPH!"

[Bruce Lancaster]

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...and Ford expected Vic's Zephyr to hit 90.

[Vic Piano]

Originally Posted by 4dFord/SC

I had to mount a magnetic placard on my 40's dash that reads, "CAUTION: Do Not Lower Windows at Speeds in Excess of 120 MPH!"

That same placard is on the inside of the glove box door on our '63 Avanti, from the factory. apparently the rear window could/would blow out at that high a speed...

[Vic Piano]

Originally Posted by Bruce Lancaster

...and Ford expected Vic's Zephyr to hit 90.

We're getting ready to install the Columbia in the Zephyr, should make a big difference in highway driving as the Zephyr came stock with a 4.44 rear.

[4dFord/SC]

Originally Posted by Vic Piano

That same placard is on the inside of the glove box door on our '63 Avanti, from the factory. apparently the rear window could/would blow out at that high a speed...

Yeah, that was the problem I had.

[JM 35 Sedan]

I run my original '35 fordor (with rebuilt 221) at 55 to 60 MPH on the Interstate highways. I took it up to 70-75 once for a few minutes just to see how it handled that speed. I think I could have gone faster but did not want to rev the engine any higher.

[sp1ke]

When I was a teenager many years ago I had a 50 ford cv. 3 speed with overdride and drove it all over the east coast of the USA and on the open I ran 70-75 and never had a problem. I am fixing to do coast to coast with the one in the picture and am planing on running the same speed.

sp1ke

[Lawrie]

We have just been up to Rocky to visit a friend in the 34 3w,stock eng with 3.54 rear gears,sat on 50- 55 mph all the way and back (120klm each way) no problems.
But the hyway was BAD and lots of B doubles, single lane each way.
Lawrie

[rickb9ol]

and thats all i have to say about that.thanx

[36tbird]

yo Vic, how come different font sizes show up with your different posts? Damn, this thread is difficult to follow.

[tierod]

36 PU wiith probably a 4:11 rear downhill with a tailwind maybe 45 mph

[oldford2]

O K to all you speedsters, Here is the next question: You are pushing your flathead to 75 on the interstate and suddenly the car entering the road cuts in front of you. To what speed do your old brakes slow you before you hit him?? Without your air bag and shoulder straps how severe will your injuries be?? hmm

[Vic Piano]

Originally Posted by 36tbird

yo Vic, how come different font sizes show up with your different posts? Damn, this thread is difficult to follow.

Ya got me??? That's a computer tech question... I have no idea Vic

[Vic Piano]

Originally Posted by oldford2

O K to all you speedsters, Here is the next question: You are pushing your flathead to 75 on the interstate and suddenly the car entering the road cuts in front of you. To what speed do your old brakes slow you before you hit him?? Without your air bag and shoulder straps how severe will your injuries be?? hmm

You're right about that John. When I'm on the highway in one of our Flatheads I usually keep to the right. I always watch for cars entering from on ramps and, whenever possible, I move to the center or left lane to avoid having to speed up or slow down quickly. Vic

[Dale Fairfax]

Why does this question/subject keep reappearing without any one knowing what R.P.M. their engine is turning? That should be the limiting factor: A late '30s car with a 4.11 rear end will be buzzing the engine a lot harder than a car with a 3.78 gear at the same highway speed. The guy with the '49-'53 car with O.D. (even with a 4.11 or 4.27 gear) is only turning 70% of the R.P.M. his gear would normally dictate. A cruising speed which spins your engine no more than 3200 R.P.M is probably the max for comfort and reliability-regardless of the roadspeed.

[Jack 34pu]

Trucks & cars are somewhat different. My 34pu has a flat grill, flat windshield etc. which equals a lot of wind resistance. It has 4:11 rear gears and at 55mph, I'm in the 2800-3000rpm range. I ran it up to 65+ once but a lot of wind noise, shakin and rattling, vibrating from unbalanced tires and somewhat wobbly wire wheels reminds me that a 45-50mph is more sensible and safe.

I have early hydraulic brakes and my wife insisted on shoulder type seat belts so she would feel safe. You must also realize that the narrow tires have a very small footprint so emergency stops can lock up the wheels but forward momentum is still maintained for some distance. I built a 34pu restorod some years back and it was much more comfortable at higher speeds. Lets face it, these old flatheads have a lot of low end torque but high speeds are not safe on most vehicles made in the 30's. So we enjoy them even with their limitations. Just my opinion.
Jack 34pu

[Joe/Ct]

Originally Posted by Vic Piano

We're getting ready to install the Columbia in the Zephyr, should make a big difference in highway driving as the Zephyr came stock with a 4.44 rear.

Vic,

You're going to love the Columbia 2-speed. We have one installed in our '39 coupe, with 78's on the rear, and just effortly cruise down the highway with no strain at all. In fact, I like to run in high range all the time (except start-ups on steep hills); does especially good in 2nd gear. (Sorry, I don't know what I've got in the rear but I believe it to be a standard banjo.)

Joe

[PeterC]

Both my 35 and 39 have Columbia's and warmed over flattys so 80 is comfortable to attain - that said - stopping is a MAJOR problem if you have a dire emergency in front of you. Both cars have juice brakes - the 39 stock and the 35 having big Lincoln Bendix units. Even so - a past experience with the 39 traveling at 65-70 when over a hill traffic was at a dead stop in my lane - there was no way my Coupe would ever halt at the rate of modern cars so my only choice was a quick move to the right lane which gave me more room to stop. I will never forget that feeling of knowing I could not haul that 39 down in time so I drive slower top end even though it is capable of faster speed.

[Kahuna]

I certainly agree with PeterC re the brake issue. My 39 coupe has the stock original brakes. They work well, but I tend to avoid hi speed in that car. The gearing is not great, as it has a 4.11 axle without overdrive. It's happiest about 55 mph. My 32, which is not quite road ready, is quite different. It has the Lincoln brakes in front and Ford 150 brakes in the rear. The car is also geared with a 4.11 axle, but has a Gear Vendors O/D. I have high hopes that it'll both keep up with traffic and at the same time stop real well. Time will tell

[lee34]

The ratio is stamped on the center section near the pinion gear.It will be the number of teeth on pinion and ring gear.A couple good ratio would be a 11/44 (4.44) or a 9/37 (4.11) lee34

[Karl Wolf]

The family station wagon was a 53 Ford, box stock... At 17 years old, I was on the way back from a flying lesson, J3 Piper... I decided to try out the old Ford, burried the speedo- it went to 100... Quite a bit faster than the plane...
Never told Dad...
Karl

[Brendan]

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50 is tops fpr my 36 pickup, i don't like to push it harder then that, also i still have mechanical brakes!

[Kurt in NJ]

39 standard --60hp ---very happy to buzz up the parkway at 70 --never finished a parade running --after 1 hour sleep --happy to do 70 on the parkway again.

[Vic Piano]

Originally Posted by Joe/Ct

Vic,

You're going to love the Columbia 2-speed. We have one installed in our '39 coupe, with 78's on the rear, and just effortly cruise down the highway with no strain at all. In fact, I like to run in high range all the time (except start-ups on steep hills); does especially good in 2nd gear. (Sorry, I don't know what I've got in the rear but I believe it to be a standard banjo.)

Joe

Thanks Joe, I'm looking forward to driving the Zephyr with the Columbia. I’ve also got a '49 Merc three speed OD transmission that I plan to install in our '53 F-100 Panel Truck. Hopefully both the Zephyr and Panel Truck will be more enjoyable to drive on the highway. Vic

[danliveshere]

When I was young and silly I would take the roadster to 100mph(59a with offy heads and twin carbs etc, 3.78 rear, hydraulic brakes). It would sit all day at 60-65 mph, never get hot, and felt good on the road. Anything over 70mph felt dangerous.Traveled nearly 70000 miles like this. Once it is restored it will be most unlikely to get over 60.... you cannot pull a car up compared to moderns with abs, etc. Plus other drivers are distracted looking at the car driving....and not where they are supposed to be. Might be a bit wiser now.

[Mike51Merc]

For a video of two flatties going somewhere in excess of 90 MPH

Go here: https://www.youtube.com/watch?v=dnG-nLwT01U

At 21 seconds is a 51 Ford Deluxe with a 239, OD, headers and two 94s

At 22 seconds is my 51 Merc, 255, OD, headers, and two 48s.

[Frank Miller]

For an accurate speed I use my GPS. Speedo in the 49 reads a hair slow. 80 is no problem. It is true what some say about handling and stopping. The only way to make them totally safe is to not drive them.

[Bruce Lancaster]

Just posted this elsewhere: Isk Dream Wheel is now reproduced for calculating your R's in a proper analog style:
http://www.honestcharley.com/iskende...-computer.html

[Ol' Ron]

There are several company's that offer a conversion to disk brakes for the stock early Ford and rather than adapt the late drum brakes, I'm going to the disks.

[Byron Warwick]

I try to avoid driving on the freeways. I run a 1954 Meteor engine with all the rest as Henry. It runs comfortable at 55 to 60 MPH. Lots of wind noise with the windshield cranked out part way. I have not driven for extended hours, but I'm going to push it for the trip to Auburn in August. Long time and going to try I-69 for the 6 or 7 hour trip.

[B-O-B]

You want to read about brakes in a situation look up rumbleseats post about his bad summer.
No one mentioned what tire combo they are running !
I ran the 34 5W with 4:11s down the interstate in the slo lane & kept up with traffic but that flatty was a hummin. Made a 50 mile one way trip to Caldwell Idaho & interstate speed limit is 75. I also had 16" wire wheels. The tires were old but had tubes so I wasn't too concerned. I do have a lap belt & wear it. Worst part was I was going to get fuel on the return trip but ran out before I got there gauge doesn't work. Not a fun way to spend a saturday afternoon on the interstate. Had to walk a couple miles to a wally world store for a can & fuel & walk back. Stupid me ran the battery down trying to prime it to start it. I only bought the small gas can(1gal) & the car was on the shoulder & listing to the passinger side & there wasn't enough gas to reach the pickup tube. When it coughed the first time I pulled the choke out to try to make it to an exit but only made it about half way so the carb was bone dry & with the car on the fairly steep shoulder the elec pump couldn't pickup the 1 gal of fuel. Lucky help finally arrived in a mercedes with a young beautiful blonde driving (NO KIDDING). Only problem was her husband was also along. She insisted on helping this old geezer & they made a couple of trips to get me fuel & a battery. I insisted on filling the mercedes (which ran on premium) & later that week I took them a couple bottles of wine. I didn't mind the expense cause it would have been cheaper than a tow job & no way was I going to leave that car parked along the side off I-84. I now carry extra fuel & jumper battery when taking that car . NOPE don't have a cell phone & don't want one.
Hope you all didn't mind my long winded hi-jack of this post.

[Kahuna]

Good story, Bob. Now, get the gas gauge fixed, cuz the odds are now against you having another "Blond" stop and help.

[B-O-B]

I have the gauge repaired just need to get home & install it. On second thought maybe lightening will strike twice in the same area. heh heh he
I spent about 30 minutes typing another incident about a couple blowouts & a female Hi-way patrol & tire warranties. I lost it so will try that one again another Day. Damn I'm whizzed.

[Gumpy]

With a 40 coupe with 3:78 rear end ratio with a 51 mercury stocker It runs 70mph

on the freeway....with quick accelaration if needed.....

[OldDad]

Here's a story from "back when" I think you might enjoy. Old Dad (my avatar, who got that nick-name working at Blair's Speed Shop here in Pasadena after the war because he was married and had a kid already at 19) was driving from Pasadena to Reno, NV on 395 late at night after work in his '33 Tudor. He had a built flathead in it with Zephyr gears, etc. He drove fast, as it was late at night and nobody on the road. Out ahead of him he spotted a couple of taillights twinkling away in the distance, which he never seemed to gain on, even though he was traveling fast. Finally, curiosity got the best of him, so he stepped it up a bit just to see what it was barreling along ahead of him. He hit 90, 95 and finally caught up with what turned out to be a cattle truck (!) that was rocking down the road. So, he just had to pull out and pass him at about 100, and blasted on by and left the truck behind. Later, he pulled into town and stopped for some coffee, and when he came back out to the car he found the hood ajar. Apparently that trucker was curious how an old '33 Ford was able to pass him that rate of speed!

My dad had a friend who used to drive back and forth from Pasadena to the University of New Mexico after the war in his '38 Tudor. He'd get out of town and then step it up to 85-90, and then pull out the hand throttle (yikes!) and use that as a prehistoric cruise control across the desert. Not recommended by me, that's for sure. Myself, 70 is about all I'm interested in driving mine. But I think it's interesting to know that these cars were certainly exercised back when they were regular transportation.

[toddle321]

My '36 Cabriolet with an LB engine and Columbia will run 75 all day without too much trouble. I have lincoln juice brakes. I've had a couple close calls similar to the guys above on the highways of Chicago, so I cruise around 60-65 and leave myself lots of room.

[Bruce Lancaster]

"39 standard --60hp ---very happy to buzz up the parkway at 70 --never finished a parade running --after 1 hour sleep --happy to do 70 on the parkway again. "

Ford performance test standards called for your 60 to be able to hit a blazing 76 MPH...buzzing though 4.44's! Your car's need for hour-long naps is a classic symptom of a dying coil; typical elderly Ford coils work fine cold, gradually cut out as they heat up, then work fine again once cool.