MTFCA Forum

Want to lighten flywheel, no mag pro an con. comets needed engine will rev faster reach higher rpm and will run smoother any one in az that can machine the flywheel

I would never consider running my T without a magneto, simply because the magneto, to me, is what makes the Model T so unique. I’m not sure about the answer to your question but I have a hypothetical, food for thought, type question:

If someone was considering illiminating the magneto by removing the magnets and mag coils for the sake of lightening the strain on the engine, since the only thing the flywheel does is hold the magnets, and starter gear ring, is there any reason why the flywheel could not also be removed? Other than the purposes just mentioned, what else does the flywheel do? Jim Patrick

I'm pretty sure others can say this better and from a position of more knowledge, but the primary purpose of a flywheel is to provide harmonic balance to the engine. Without it there would be a lurch every time a cylinder fired. It smooths things out using the inertial energy of the flywheel weight.

Maybe someone else can explain it better......

Be careful how much you remove. I know of some Model A guys that lighten their flywheels and had hard time going up hills. That flywheel is there for inertia. They changed back to standard flywheel and go right up over hill with no lost of speed. Dan

You lighten a T flywheel and assembly by removing the magnets, clamps, and spools and screws, taking off approx. 18lbs.

Then you can lighten the flywheel itself by removing center mass material, to what ever weight you want to remove., but keep in mind you need a 'flywheel effect'.

The flywheel effect is from the outer diameter anyway. It is needed to keep continued smooth rotation of the engine.

A light flywheel is desired in fast acceleration, like on dirt tracks coming out of the turn. And at high speeds there are the rest of the rotating parts do provide good effect, so the heavy flywheel isn't missed.

With normal stock flywheel in a T, with the magnets providing ignition the stock weight allows smooth running, for each power impulse in high at normal T road speeds. That is normally just fine. The stock set-up provides good torque too at low speeds, for hills.

For a racer or speedster, you can make it quicker off the line with removing the magnets and field coils. Plus there is some, perhaps hard to measure, drag of the magnets over the field coils too.

Once did a speedster and removed the magnets, added flippers for oil sling, as it was an early flywheel w/o ring gear. The body was just plywood deck and 2 buckets, gas tank, and tool box with 12v storage battery inside for ignition to the coil box and plugs. That thing was swift in low gear and in high too. Could feel the difference.

I suppose a good example that demonstrates the necessity for a flywheel can be found on a 19th century steam engine. Jim Patrick

On my 1915 Case 65 HP steamer most of the flywheel requirement is for the clutch and the fact it is used as a flat belt pulley. Consider that the engine is double acting so it has 2 power strokes per revolution.
Steam train locomotives here 4 power strokes per revolution.
My 1913 Stanley has virtually no flywheel as it again has 4 power strokes per revolution.

Ignoring all of my above the T certainly needs significant flywheel in my opinion.

DanTreace wrote: ↑

Thu Apr 02, 2020 1:37 pm

Then you can lighten the flywheel itself by removing center mass material, to what ever weight you want to remove., but keep in mind you need a 'flywheel effect'.
The flywheel effect is from the outer diameter anyway. It is needed to keep continued smooth rotation of the engine.
A light flywheel is desired in fast acceleration, like on dirt tracks coming out of the turn. And at high speeds there are the rest of the rotating parts do provide good effect, so the heavy flywheel isn't missed.
With normal stock flywheel in a T, with the magnets providing ignition the stock weight allows smooth running, for each power impulse in high at normal T road speeds. That is normally just fine. The stock set-up provides good torque too at low speeds, for hills.
For a racer or speedster, you can make it quicker off the line with removing the magnets and field coils. Plus there is some, perhaps hard to measure, drag of the magnets over the field coils too......

Dan, Thank you for proving an unbiased explanation for the purpose of modifying the flywheel and satisfying the criteria of Les' request. My interest in reading posts is to increase my mechanical knowledge.

Rich Huggins wrote: ↑

Thu Apr 02, 2020 7:34 am

Want to lighten flywheel, no mag pro an con. comets needed engine will rev faster reach higher rpm and will run smoother any one in az that can machine the flywheel

You don't have to physically machine the flywheel to remove weight. if you're going with a distributor then you can remove the magnets and substitute paddles to keep the oil lubricating engine. Naturally flywheel would need to be balanced in this configuration to make it smooth.