Lightened Flywheel ???

[festivaWES]

We did it on a brake lathe. Or you could have a machine shop do it but labor isnt cheap.

Most machine shops around here will NOT lighten a stock steal flywheel because of liability reasons. It's either you have the lathe and do it yourself, or know a friend who has one that doesn't care about liabilities.

[fastivaca]

I'm running the FMS flywheel behind a B6 and love it. It revs a little faster and if there is any torque loss I'd haven't noticed it.

[FestYboy]

factory flywheel is ~ 16 lbs. i had 6 lbs removed and there's a huge differance.

flywheel weight doesn't affect torque production, EVER.

[gorgonheimer]

not torque production but it will affect the amount to the wheels. the more rotational mass the harder it is to stop. the feel of it will change, it will bog more when not in the upper range. the same is true for huge oversized wheels, they are harder to stop and take more power to turn affecting acceleration and braking.

dont get me wrong it is a great mod and he will love it

[FestYboy]

^ correct!

[blkfordsedan]

It's all about inertia. Less flywheel weight will augment the compression hold-back of the engine (car will slow down quicker when you let off the gas in gear). It will also help acceleration due to the less mass it needs to accelerate. The oversize wheels are a good analogy. A good rule of thumb for street car use is 1Lb of flywheel for every 100Lbs of car weight (4000# car needs 40# flywheel). Maintaining cruising speed and drivability will be effected, but the feel will definitely be more "race car" like and a lot more fun to drive! BTW, a similar effect can be had by turning down the counterweights on the crankshaft and having it rebalanced using heavy metal plugs. It's the same theory behind all lightweight dynamic engine components like rods, pistons, valvetrains, etc.

You may also want to consider a steel scatter-shield if your not using a quality aftermarket flywheel. Especially given the transverse mounted engine and the thin metal of the Festiva firewall.

[Biglay5150]

Im using a Quality Factory flywheel.lol We did it in a way that did not take away from the integrety or strength of the flywheel. We just took off excess metal.

[blkfordsedan]

Sounds like you should be fine. You just never know about things some people will do!
I had a friend in high school with a '55 Chev and a 327 4 speed combo. It ran mid 14's, but the one time he took it to an actual track the flywheel grenaded on the 2nd pass. Granted, it had years of abuse, but after seeing the damage done to the bell housing and block, I still get scared thinking about it! Personally, I would put a scatter shield on any kind of race car (even a Festiva) where the flywheel is subject to high RPM or abuse.

[gorgonheimer]

so i say go for it and have fun. keep us posted as to your findings. oh and we love video

[ejp2fast]

one more thing for all you experts.. and slightly off topic..

when driving our 2006 corolla S 5spd when you go to shift, (push in clutch, shift gears, revs drop, clutch out) the revs drop MUCH faster than any car i've ever driven... its like i have to speed shift to match the revs because they drop so fast... now, my festiva, when shifting.. is normal.. and a little slow.. gives me time to shift smooth and let the clutch out...

does this mean the Corolla has lighter engine components (crank/ flywheel) or whats up here?

[Biglay5150]

Got my flywheel back today. Cant wait to install it. I cant imagine this thig was balanced from the factory. It is now.

[blkfordsedan]

Got my flywheel back today. Cant wait to install it. I cant imagine this thig was balanced from the factory. It is now.

It should have a "0" balance. I wouldn't think FMS (or anyone else) would sell a flywheel that is not balanced within factory spec. In theory, turning it down on a lathe should not effect the balance. If you want a truly balanced motor you would need to have the entire rotating assembly done as a set anyway (pistons, pins, rods, crank, flywheel, timing pulley, balancer and belt pulley).

[festivaWES]

one more thing for all you experts.. and slightly off topic..

when driving our 2006 corolla S 5spd when you go to shift, (push in clutch, shift gears, revs drop, clutch out) the revs drop MUCH faster than any car i've ever driven... its like i have to speed shift to match the revs because they drop so fast... now, my festiva, when shifting.. is normal.. and a little slow.. gives me time to shift smooth and let the clutch out...

does this mean the Corolla has lighter engine components (crank/ flywheel) or whats up here?

I don't even let off the throttle when shifting when I'm racing.

[econoaddict]

Got my flywheel back today. Cant wait to install it. I cant imagine this thing was balanced from the factory. It is now.

I looked at the stock one you dropped off at the shop and found no evidence of balancing of any kind.

I may send it out and have the balance "checked" just for fun.

I am curious as to how much the balance changes when we lighten them.

[Biglay5150]

^^ thats what Im talking about. If we shave it off on a lathe the balance should not change much. But then why would in need so much off one side to be truly balanced? On an internaly balanced motor you shoulnt need to balance it all as a unit. And if you did than what happends when your starter tears up your ring gear and you have to replace the flywheel. Im just thinking "Factory specs" arent very tight and now it is truly balanced.