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.