Lightened Model A Flywheel

[old28]

Trying to figure out how much weight to take off a Model A flywheel for my TROG race car. Car will be run in side by side 1/8 mile beach drag races only. Motor will be around 75-85 HP with a B trans case with late model gears. going to run a 9" clutch, 4.11 rear gears.

Would like to make the flywheel as light as is safe and one that will hold up.

[Ron in Quincy]

I am running a 37 pound, including ring gear, cut down A flywheel and V8 clutch. My engine is touring engine with about 55 horse power; I have 3.54 gears in the rear end. I know a man that had a Riley overhead powered A that he used for racing, it had a 12 pound aluminum racing flywheel, no ring gear, and push to start.

Be sure to have you flywheel balanced after cutting it down to what ever weight you decide to go with.

Ron

[JohnLaVoy]

I think I'm at 34 pounds on mine and that was done by an old racer back in the 60s!

[BRENT in 10-uh-C]

In essence, the lighter the better for that application. I had one in a speedster that I raced that weighed 23#. I think I still have that one, and if you are interested in that one, contact me off-line.

[Bob Bidonde]

The physics of inertia rules. Mass remains in its current state unless acted upon by a force or system of forces. In this case, it takes more energy to accelerate and to decelerate a heavier flywheel.

[BILL WILLIAMSON]

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Anyone ever cranked up a Model A, without a FLYWHEEL? What was it like?
Bill W.

[old28]

B Terry -- "Interested" I left a message on your answer machine. I will try getting hold of you again on Monday.

Thanks Guys for all the replies. For the type of racing I want to build for I think a mid 20's pound flywheel would work out fine with a 9" V8 clutch.

[PC/SR]

Dan Price in Ohio was making 27 lb wheels. Very nice. Check with him.

[BILL WILLIAMSON]

How come NOBODY answers Post# 6?
Bill Paranoid

[ratamahata]

The one who cranked out had missed the arm!!! 😂

ratamahata

[Terry, NJ]

Bill, I seem to recall someone saying that they had run a Mod A with out a flywheel. Surprising! To go from a 63 Lb rotating mass to zero and it still ran is almost unbelievable. Some how I think that to try to tax any of the power away would probably kill it immediately.
Terry

Originally Posted by BILL WILLIAMSON

How come NOBODY answers Post# 6?
Bill Paranoid

[harleytoprock]

It was "Pete" who said a Model A can be hand cranked to start and will idle at 400 rpm with no flywheel.

[b.j.]

installed a 1953 mercury flywheel, on a modified engine, with the late model clutch assembly, starter drive has to be turned around (backwards) to engage the ring gear. don't remember the weight, fun "stuff"

[BILL WILLIAMSON]

Originally Posted by Terry, NJ

Bill, I seem to recall someone saying that they had run a Mod A with out a flywheel. Surprising! To go from a 63 Lb rotating mass to zero and it still ran is almost unbelievable. Some how I think that to try to tax any of the power away would probably kill it immediately.
Terry

Terrance,
I only asked the question, like if you had a spare engine, in a "crate" like box, just cut a crank hole & fire it once in awhile, to keep it running good.
Bill W.

[Jim Brierley]

9" clutches work very well, but you might also consider a diaphragm clutch. /These are much smoother. Not as important on a racer but is on a street-machine.

[old28]

Jim Brierley -- As this TROG car will be for the race only and not be on the street, my thought was that the 9" clutch was the better deal and would have less slippage. This is also why I am thinking a light 20-28# flywheel will work best.

[40 Deluxe]

A friend has said that when he was a kid in the late '40's-early '50's, the fastest car across an intersection was a stock Model A, due to that heavy flywheel! Just wind it up and pop the cutch when the light turned green. All that stored energy made you leap across!

[Jim Brierley]

What 40 deluxe says is true but after getting across the intersection, a heavy wheel is a detriment. The 9" Ford clutch is good for what old28 wants to do.

[old28]

40 Deluxe -- Trans gearing added to that intersection win also.

Jim Brierley -- Do you think a 20-27# flywheel is do-able for my project with a 75-85 HP motor, 40-48 trans gears in B case and 40-48 Banjo rear with
4.11- 6.17 gears? The race is only 1/8 mile.

[BRENT in 10-uh-C]

Originally Posted by old28

B Terry -- "Interested" I left a message on your answer machine. I will try getting hold of you again on Monday.

Thanks Guys for all the replies. For the type of racing I want to build for I think a mid 20's pound flywheel would work out fine with a 9" V8 clutch.

I finally dug out the flywheel I was speaking of. It is set-up for a stock type pressure plate. I suppose I/someone could machine it for a modern V8 style PP. Here are some pix. The last picture is the car I ran it in.

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