backfiring and not much power

you need to go over this car properly,start with the basics and reset/ clean and or replace the points/condenser and reset the timing to proper specs. possibly also go through the carb by cleaning it out or getting one from berts which are reasonable "the guys have had good reports of them".
 
Morning people, my story goes like this. After having to flat bed my Coupe back to my garage, maybe a half doz. Times, and I was close to scrapping her, I called this old guy wok has worked on A's for 70 + years. After many trials and tests, we found a small piece of metal under the upper plate in the distributor lol. Problem solved no more back firing or loss of power.
 
Gino said:
Morning people, my story goes like this. After having to flat bed my Coupe back to my garage, maybe a half doz. Times, and I was close to scrapping her, I called this old guy wok has worked on A's for 70 + years. After many trials and tests, we found a small piece of metal under the upper plate in the distributor lol. Problem solved no more back firing or loss of power.
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would that small piece of metal be part of a modern lower plate with the brass contact??? they cause that exact problem
 
We say it all the time here don't think any one said in this post. Find and join your local model A club. There is a good one in your area, they will be eager to help you. They have a wealth of knowledge.
 
Since we're talking about spark advance etc...

DOes anyone know what the octane rating of the gaslone would have been in the 20's/30's???I've read 60-80, but have nothing solid.

I'm expecting it was a lot lower than it is now (Many old cars specify FAR lower required ratings than any modern fuel has, I've seen 50's cars that required 72 octane and similar), so if you still have stock compression, the lever can probably be pulled further down without problems, couldn't it? It would be far less prone to pre-ignition.

Once cruising on any flat road (45 MPH or so) I run it between full advance and a couple of clicks up. I move it closer to half on steep or long hills.

I know I don't want to run it too retarded either, because the exhaust gas temperature skyrockets and you start risking over heating, or cracked heads and saggy exhaust manifolds.

I wonder if Henry's advice in the book still applies less with more modern fuels and higher octane ratings?
 
Check joint between carb and manifold, and if you have an air leak in carb.


I had a bad gasket and a warped Tilly top half. Very lean, no power, lots of GAV.

Lean test is to gently downshift while coasting downhill. Popping=LEAN.
 
ctlikon0712 said:
This is what Henry told the new purchaser of the Model A's about driving and timing advance....
127194
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Interesting thought here- Back when A's were new gas was 60 octane on a good day, and you could probably easily get audible spark knock with too much advance, even with the 4.22CR. That must have made it easy to learn how to play the advance lever.

With today's worst gas at 87 octane full advance at 4.22CR may not produce any spark knock, but will certainly present too much cylinder load while still on the upstroke. Not readily detectable by ear, you now need a very good 'feel' for how the engine behaves. Not everyone has that fine touch.

The learning curve is steeper today than back when.
 
MikeK said:
Interesting thought here- Back when A's were new gas was 60 octane on a good day, and you could probably easily get audible spark knock with too much advance, even with the 4.22CR. That must have made it easy to learn how to play the advance lever.

With today's worst gas at 87 octane full advance at 4.22CR may not produce any spark knock, but will certainly present too much cylinder load while still on the upstroke. Not readily detectable by ear, you now need a very good 'feel' for how the engine behaves. Not everyone has that fine touch.

The learning curve is steeper today than back when.
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I never though of this!! Could this be the reason I blew the #3 big end at 45 mph a few years back with the advance all the way down?

Recently, I've found the car runs better on the street at 8:30 to 9:00 rather than 7:30.
 
Yep, what Mike just said. It takes a little practice and some feel. But, playing with the spark lever will produce a noticeable difference in what the engine likes and dislikes without ever hearing detonation/spark knock.
 
Your best advice is to find someone in the San Antonio area that can look at your car for you. I'm sure there is a local Model A club that you could attend a meeting. Your condition could be caused by a variety of maybe or not so maybe obvious causes. Not knowing the history of your car you should at least start with a compression test of the engine, check fuel flow and the ignition system.
 
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