Top speed or lack of

[Terry, NJ]

Yesterday we had to pick up my Saab from Pa inspection and we went over in My 1930 coupe. Coming home, I tested the top speed (Speedometer doesn't work). The best was 45 MPH. Engine runs good, GAV is closed, Brakes are not dragging, engine seems cool when I stop. Everything seeds ok . However, My wife commented that the engine seems to be working very hard, I agree. I'm new to mod A's, so I'm not sure. However, The 60MPH that I read about is a far and distant dream.
Terry

[Mike V. Florida]

First thing I found out that limilted my A from going above 45 was the timing. Once I re adjusted it and really took my time, 60 mph was obtainable.

[Logan]

Most stock A's won't run 60. If they do run 60 most of the time they feel like the pistons are swapping cylinders at 60. 45-50 is normal for a comfortable driving speed in a stock A with 3:78 standard gears in the rear end. Although I'm not sure why you closed the Gav, I usually run on about 1/4-1/2 a turn open. I'm not saying if you open it up a little that you will see 60 mph, but you are running it to lean unless you live in high elivation. Check your timing and make sure it's correct, if you're not forsure, check it with a timing light.

[Phred]

The first thing that comes to mind is to open the GAV more at road speeds. The car may idle fine with closed GAV, but everybody under the hood might prefer a richer air-fuel mixture at speed.

Ignition timing may also be off, more advance for road speeds.

Hope this helps

[V4F]

still i think your timing is slow .

[gweilbaker]

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Check that the throttle has full range of motion. I've seen as much as 50% loss due to wear and being bent.

[29ModelA]

When I had issues it was timing, same with a friend around the corner with his. I put the pin and the dimple and pointed the rotor as so, and now I can hit 60 but as stated it sounds like the engine wants to come apart.

[jkeesey]

I had a retarded timing issue when I first had mine on the road and it showed the same symptoms. Now that ive got the timing set properly, even with my 600x16 tires she does 55 with no hesitation and I could push it more but its not too safe on our back country roads.

[Tom Wesenberg]

Originally Posted by 29ModelA

When I had issues it was timing, same with a friend around the corner with his. I put the pin and the dimple and pointed the rotor as so, and now I can hit 60 but as stated it sounds like the engine wants to come apart.

The picture shows the rotor in the ADVANCED position.

When the pin drops into the cam gear dimple the rotor should be on the trailing edge. The rotor turns CCW.

[Purdy Swoft]

Tom is right!!! the timing is off, the width of the tip of the rotor, providing that there is no clockwise backlash. Lock the points cam down with the trailing edge of the rotor tip pointing at the number one contact in the cap body with no clockwise backlash. You have the leading tip of the rotor aligned with the contact in the cap body. You will see a noticeable difference in power and speed if you correct the timing adjustment..

[Jason in TX]

CLICK HERE FOR MODEL A TIMING INSTRUCTIONS

Print multiple copies of this page out... hand it out to your model A friends, keep a copy under the seat, memorize it, dream about it... It's the Model A gospel.

Learn how to time your A on the side of the road with a flat head screw driver and a crescent wrench. You will be happy you learned this




The rotor position shown above is the proper position with the timing pin in the gear depression and piston #1 at TDC. The dashed line shows the position of the rotor when #1 fires with the spark lever fully advanced (down).

[P.S.]

All this wwithout knowing what gears he has in the rear end? If he has 4.11 gears back there, 45 MPH will be about tops.

[Mitch//pa]

terry you got something wrong, is your throttle linkage fully opening the carb. i would figure it out before you hurt something

[heneste]

As P.S. has mentioned, gear ratio can also be your limiting factor. I know my car has a 4.11 gear and the car will hit 45 but you'll really be feeling it with the vibration and engine revs.

The GAV should also be open somewhat otherwise you're restricting the engine of extra fuel it needs at speed.

As you don't mention you had any wheel noise or tranny noise, I'll assume that everything is greased sufficiently and not causing any dragging on the powertrain.

[29ModelA]

Originally Posted by Tom Wesenberg

The picture shows the rotor in the ADVANCED position.

When the pin drops into the cam gear dimple the rotor should be on the trailing edge. The rotor turns CCW.

When I ran mine any more retarded than that the car would barely run, and the exhaust would glow a nice shade of red.

[Purdy Swoft]

I think that you are still running retarded. It fires when the points open. You've got nothing to lose. Set the rotor tip as Jason shows in post number 12 and if you really don't see a big improvement you can easily put it back like it is. I'm surprised that it even cranks, the way that you've got it.

[Tom Wesenberg]

Originally Posted by 29ModelA

When I ran mine any more retarded than that the car would barely run, and the exhaust would glow a nice shade of red.

That is possible if you are running a different set of points or upper plate. I've read that some of the "modern" upper plates located the points incorrectly, so when they just started to open, the rotor was off from where it should be.

I've always had the best luck by only using original points and top plate.

[Special Coupe Frank]

My tired, stock '28 Special Coupe will achieve 60-65, flat-out on a good day.

I usually run with the GAV 1/4 to 1/2 turn open.

It sure sounds busy at those speeds.

It is much happier below 50 mph.

[Mike V. Florida]

Originally Posted by Logan

Most stock A's won't run 60.

You're right most won't, but just because they won't does not mean they can't!

[Purdy Swoft]

If they are not properly tuned they sure won't run 60 mph.

[29ModelA]

Originally Posted by Tom Wesenberg

That is possible if you are running a different set of points or upper plate. I've read that some of the "modern" upper plates located the points incorrectly, so when they just started to open, the rotor was off from where it should be.

I've always had the best luck by only using original points and top plate.

PMed you as to not totally highjack the OP'ers thread.

I have GPSed mine at 58/59mph but I ran out of road to squeak that extra out of it. Because it would run that speed I figured I had it right.

[BILL WILLIAMSON]

Old, tired, (soft) valve springs will limit top speed also. Bill W.

[Tom Wesenberg]

Originally Posted by 29ModelA

PMed you as to not totally highjack the OP'ers thread.

I have GPSed mine at 58/59mph but I ran out of road to squeak that extra out of it. Because it would run that speed I figured I had it right.

This should fit in with top speed, because timing is everything.
I would hand crank the engine until the timing pin just drops into the cam gear dimple. Someone said some gears had the dimple in the wrong place, so that could also be a problem, but only with initial timing. Anyway, when the timing pin drops into the dimple, the piston should be at TDC and the trailing edge of the rotor should be next to the #1 contact and the points should just be ready to open. Be sure the spark lever is all the way UP, and the points are set to .020", then do the timing.

These could cause the rotor to be in the wrong place in relation to the points just ready to open:
1. The alignment tab in the rotor could be off, but I've never heard of this being a problem.
2. The points could be located in the wrong place on the top plate. I've heard of this when some repro parts were used.
3. The distributor cam notch could be in the wrong position, though I haven't heard of such a problem.
4. The rubbing block on the points arm could be located wrong, but I've never heard of this being a problem.

Someone reported that the dimple is sometimes drilled in the wrong place on the cam gear, though I haven't encountered this problem yet. This could affect the spark timing, but won't affect the relationship of the point opening and the rotor tailing edge being next to the #1 contact.

[Purdy Swoft]

With no clockwise backlash.

[31 A4door]

My 26 T now pulls hard at 54 on the GPS. A little scary with 90 year old wood wheels. I have just a few mods to it though. heh heh.

[P.S.]

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Originally Posted by Jeff/Illinois

THAT might be what's messing me up. I have a set of modern points on a repro upper plate.

Going back to original they are easier to set the points anyway.

Good thinking. Tom talked me into going with original setup and the Tudor has been running like a watch ever since. SO GLAD I listened to Tom. What a difference.

[MikeK]

If the engine was rebuilt and has a reground cam from the Sears/ Wards/ JCWhitney era you are lucky your car does 45. A bad regrind is the #1 horsepower and drive-ability killer.

[Purdy Swoft]

Originally Posted by Jeff/Illinois

Purdy this is what always confused me.

The rotor turns COUNTERclockwise so wouldn't the opposite be true, the backlash is taken out on the counterclockwise direction? Otherwise you have slop in the clockwise direction that makes the rotor 'off' when it is turning CCW?

Counter clockwise backlash has no effect on timing because the distributor shaft, points cam and rotor ride on the clockwise end of the backlash. In other words if the points cam is tightened and clockwise backlash remains, when the backlash is taken up by the turning shaft, you will end up with the timing being retarded the same amount as the clockwise backlash that was allowed to remain when the points cam was tightened. This can be hard to explain but is one of the main reason that so many model A's are running at way less than their real potential. I'm not tring to be a smart azz, just tring to give as clear of an explaination as I can.

[eagle]

If it sounds like the engine is laboring, check timing. If it is running out of RPMs, check your rear end ratio. By you posts description I would check timing. My engine pulls a heavy Fordor with 4 adults and 2 kids 55 easily. I usually run about 48-50 because it feels best there. Its all stock, Zenith carb, std head, std everything. Just for your own peace of mind, advance the timing so the engine pings, then back off just until it stops. You should have plenty power then.

[40 Deluxe]

As a suggestion, some thoughts here might be confusing to a newbie to A's. The .020" point gap setting is done with the points rubbing block set on the highest part of the cam lobe (don't set the timing pin in the cam gear dimple yet). Just crank the engine until the points are open the widest. Now set the gap to .020". Next get the pin in the dimple by turning the engine in it's normal rotation. Don't worry about the rotor's exact location. The rotor does not control the timing! The instant of point opening is the magic moment. The rotor just has to be in the general vicinity of the #1 spark plug terminal. So; pin in dimple, spark lever fully up, points just barely open is correct timing. To adjust,"loosen the cam locking screw and turn the cam counterclockwise until the points are fully opened, then slowly turn the cam back in a clockwise direction until the points just close. Hold the cam from turning and tighten the locking screw. This method prevents any backlash in the distributor shaft from affecting the timing." Note: the quotes are from the Model A Instruction Book.
Here is the Ford method for checking your work. Quoting again: "Withdraw the timing pin from recess in timing gear. Turn on the iginition switch. Again insert the timing pin into opening in gear cover. While turning the engine over with crank, press in on pin. If properly timed, just as the pin seats in the recess in the timing gear, a spark should accur between the breaker points. If a spark does not occur, some error has been made and it will be necessary to recheck your work until the spark occurs between the breaker points as previously described." Not mentioned in the book, but you will see a spark when each cyklinder fires as you are cranking the engine through two full revolutions. Just make sure you see the spark at eactly the same time as the timing pin hits the dimple.

[Chuck Sea/Tac]

CHECK YOUR STEERING COLUMN. If its twisted, both throttle and advance can be limited!!
Chuck

[Terry, NJ]

Well Guys, I fittiddled around with it. I cut my teeth on 49-53 flatheads and mod As are strange! Adjustable Cams? What were they thinking of? Anyway, It turns out I should have left it alone. It was probably set perfectly. The points were. Right on .020! The engine wouldn't cooperate, Everytime I cranked past the cam gear dimple. Not far past, but just enough. Put her in 3rd and rock it back. The hell with this! I used dead reckoning. A small flashlight in No1 cylinder. I could see TDC. Then I recalled an old trick I hadn't used in years. I loosened the cam lock screw and rotated the cam till the points sparked (Ignition On) I got it close but not right. It seems slightly retarded to me. The engine runs much hotter, an d has even less power. I'll spend tomorrow straightening it out.
Terry

[dumb person]

Originally Posted by gweilbaker

Check that the throttle has full range of motion. I've seen as much as 50% loss due to wear and being bent.

Good point, i never saw one that got %100 yet.

[40 Deluxe]

Terry, are you using the hand crank to rotate the engine? 'Bumping' the starter usually doesn't work well.

[Terry, NJ]

Originally Posted by 40 Deluxe

Terry, are you using the hand crank to rotate the engine? 'Bumping' the starter usually doesn't work well.

Yes, I'm using the crank. The motor is tight and you have to pull so hard with the crank, then it spins......right past the dimple! Not far, but just enough to mess you up! A real PITA. Then it's put it in third and rock it back.
Terry

[Banky]

I updated to modern points when I was overhauling everything. This being my first A, I've never run it with the old points. That being said, EVERYTHING TOM HAS ADVISED ME ON HAS BEEN 100%. Gonna swap them out to see if I get better power up hills. I'm not looking to set land speed records by any means, but huff hills better.

[Purdy Swoft]

Originally Posted by Terry, NJ

Well Guys, I fittiddled around with it. I cut my teeth on 49-53 flatheads and mod As are strange! Adjustable Cams? What were they thinking of? Anyway, It turns out I should have left it alone. It was probably set perfectly. The points were. Right on .020! The engine wouldn't cooperate, Everytime I cranked past the cam gear dimple. Not far past, but just enough. Put her in 3rd and rock it back. The hell with this! I used dead reckoning. A small flashlight in No1 cylinder. I could see TDC. Then I recalled an old trick I hadn't used in years. I loosened the cam lock screw and rotated the cam till the points sparked (Ignition On) I got it close but not right. It seems slightly retarded to me. The engine runs much hotter, an d has even less power. I'll spend tomorrow straightening it out.
Terry

Terry, just trying to help. When trying to find the timing dimple, it is best to first remove the spark plugs. Its hard to keep from going past the dimple when fighting the compression with the plugs still in place. Checking for TDC
with a flashlight through the plug hole is not an acurate method because the pistons rise above deck height. I always check point gap before doing anything. The recommended gap is .018-.022. .020 is a happy medium setting. I set mine on .022 because this gives slight timing advance and gives more time before the points will have to be reset because of rubbing block wear. I think that when you loosened the cam screw and turned the cam until the points sparked, you cranked in clockwise backlash, that caused you to be running more retarded. Remember that the distributor turns counter clockwise when the engine is running but rides on the clockwise end of the backlash. When the cam screw is tightened, there must be NO clockwise backlash, the points must be just ready to open. To check this, fully retard the spark lever, turn the ignition on, with a good fitting screwdriver in the cam screw , with the cam tight against the end of the clockwise backlash , Turn the cam screw counter clockwise not to loosen but to watch for a spark at the points. You shouldn't have to move the cam screw but a small fraction to see a spark. This is the test and if you have to move the cam screw much before the points spark, this will indicate that you still have clockwise backlash and the timing will be retarded. Another important thing to look for, is whether you have full movement of the upper plate. The arm on the upper plate that the spark linkage connects to needs to make contact with the right side of the window in the distributor cap body when the spark is retarded, it needs to contact the left side of the window when the spark lever is advanced. If you are not getting full movement of the upper plate, loosen and rotate the steering column tube untill you get full movement. If you don't get full movement of the upper plate when the spark lever is fully advanced, you will still be running retarded no matter how the timing is set. I hope that this makes sense

[Tom Wesenberg]

What Purdy said!
Also if you don't have the special cam adjusting wrench, you need to buy a couple. Keep one in the car and hang one in the shop. They're only about a dollar each. It's much easier to adjust the timing accurately with the wrench.

[P.S.]

This thread got me thinking....

Just for grins, I ran the Tudor with the timing just barely down from all the way up (TDC) and put my "foot in it" to see how fast it would go. Even with the spark advance only 2 notches below TDC, made 55 MPH, no problem. No O/D or higher gear ratio, totally stock.

So... my question is... Since a Model A will do near top speed with the timing fairly retarded, why do we keep sending "29ModelA" down this path to nowhere? Can someone come up with some other ideas and stop harping on the timing thing?

O, I can hear it already... Maybe my tudor's timing isn't set right, etc. The timing is set exactly right on, don't even go there. Les Andrews himself stood behind me and watched me set the timing on a car at a tech seminar late last year and said that I was doing it right. NEXT!!!

[MikeK]

Hello? post #27

[P.S.]

Originally Posted by MikeK

Hello? post #27

Right!

[Terry, NJ]

Originally Posted by MikeK

Hello? post #27

I'm not sure what you mean. Post #27 is about camshafts. It has the cam that came with it and I have no way of knowing who made it. After a llot of fooling around with it, It seems to run pretty well now. It hasn't been on the road yet but I'll try as soon as possible. I'm beginning to think maybe the camshaft/valve springs are the culprits. I won't get back to it for a couple of days and I'll update you all about it then.
Terry

[Purdy Swoft]

Originally Posted by P.S.

This thread got me thinking....

Just for grins, I ran the Tudor with the timing just barely down from all the way up (TDC) and put my "foot in it" to see how fast it would go. Even with the spark advance only 2 notches below TDC, made 55 MPH, no problem. No O/D or higher gear ratio, totally stock.

So... my question is... Since a Model A will do near top speed with the timing fairly retarded, why do we keep sending "29ModelA" down this path to nowhere? Can someone come up with some other ideas and stop harping on the timing thing?

O, I can hear it already... Maybe my tudor's timing isn't set right, etc. The timing is set exactly right on, don't even go there. Les Andrews himself stood behind me and watched me set the timing on a car at a tech seminar late last year and said that I was doing it right. NEXT!!!

Tell that to somebody that doesn't know anything about a model A and they might believe it. I for one know better!!!

[BCCHOPIT]

Do you know what lifters are in the engine?
If you have the cheep 1" lifters you will loose
A lot of power. It will be like having a shity reground
cam.
But if you have 4:11 gears you will never get
Any speed out of it.

[BILL WILLIAMSON]

Originally Posted by Purdy Swoft

Tell that to somebody that doesn't know anything about a model A and they might believe it. I for one know better!!!

You got that RIGHT, Brother Purdy! If a stock Model A will run 55 with spark down ONLY 2 knotches, the initial timing was set too much ADVANCED!!!
Quick test on a stock Model A:
1-Spark up= a smooth rythimical--TADA-TADA-TADA-TADA!
2-Spark 1/2 down= a smooth, higher RPM idle!
3-Spark Full down= an even higher RPM, but a somewhat "ROLLING" IDLE!
If you have ALL the above, it's PERFECT, so QUIT messin'& doodlin' with it.
AND A MODEL A DOESN'T "JUMP TIME" or the timing doesn't just "SLIP" unless the cam lobe screw is loose, or the washer is missing under the screw!! HAPPY MOTORING bILL w.

[Purdy Swoft]

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Thanks Bill!!! I figure if the initial timing was set, that advanced, you would probably have to push it off to crank it. It would probably buck like a young mule at low speed and the spark lever would be useless. It still wouldn't run 55.