alluminum flywheel?

[902066]

If you have a lightweight flywheel in your ZR-1, do you love it, or hate it, and the reasons why? I am seriously thinking of adding one but am on the fence. I do have 4:10s, stainless works headers and corsa exhaust. I would think these 3 should help if I go with the flywheel. Thanks Jim

[BigJohn]

You would never feel the difference!
Lighter rotation mass; engine should Rev quicker

[conesare2seconds]

No thanks.

[Demps]

I?d ask a few questions back to make sure that I answered your question correctly:

How do you use the car? Street, drag, track?
Will you do the work yourself or outsource it?
Do you mind holding the clutch at stoplights?
Do you mind weird gearbox rattle?
Would you like quicker revs?

Not trying to be snarky. I like them but they come with sacrifices.

Not knowing the answers above here?s my stab:

If you can do it yourself yes.
If not, have the top end ported & new chip/tune.

Ted

[902066]

Originally Posted by Demps

I?d ask a few questions back to make sure that I answered your question correctly:

How do you use the car? Street, drag, track?
Will you do the work yourself or outsource it?
Do you mind holding the clutch at stoplights?
Do you mind weird gearbox rattle?
Would you like quicker revs?

Not trying to be snarky. I like them but they come with sacrifices.

Not knowing the answers above here?s my stab:

If you can do it yourself yes.
If not, have the top end ported & new chip/tune.

Ted

I'll try to answer your questions. I am basically a waxer and a cruiser. the work will be outsourced but a lot of other things are being done at the same time. I always hold the clutch at stoplights. I could live with some gearbox rattle, just not real loud and only somewhat annoying. Whats not to like about quicker revs? Its probably not real practical for me, but unless someone absolutely hates it and can tell me why, I'll probably do it. Thanks for your reply.

[Zman]

Here are my thoughts about your situation. I have a 368 with 4:10S and an aluminum flywheel. The car is bat chit crazy! But, I feel 4:10S or an aluminum flywheel is a better combo. I say this because I have a 385 with 4:10S with a stock flywheel and at times this is too much. I agree with keeping the stock flywheel with 4:10S. The reason I say this is because an aluminum flywheel is a crap shoot as to how rattlely it will sound. It will allow your RPMs with 4:10s to be gone too quickly. I wouldn?t do it. Both do about the same thing as for drivability but too much of a good thing is not always best. Like Demps said....port and chip.

[902066]

Originally Posted by Zman

Here are my thoughts about your situation. I have a 368 with 4:10S and an aluminum flywheel. The car is bat chit crazy! But, I feel 4:10S or an aluminum flywheel is a better combo. I say this because I have a 385 with 4:10S with a stock flywheel and at times this is too much. I agree with keeping the stock flywheel with 4:10S. The reason I say this is because an aluminum flywheel is a crap shoot as to how rattlely it will sound. It will allow your RPMs with 4:10s to be gone too quickly. I wouldn?t do it. Both do about the same thing as for drivability but too much of a good thing is not always best. Like Demps said....port and chip.

Makes a lot of sense. I think I'll take advice from both of you and keep the stock flywheel. Jim

[Zman]

I think you have the perfect combo if you were to port and chip your car.
Ported, Headers, 4:10s, chip and tune. Perfect. Much more you will lose your street driving enjoyment in my opinion.

[dredgeguy]

Originally Posted by 902066

If you have a lightweight flywheel in your ZR-1, do you love it, or hate it, and the reasons why? I am seriously thinking of adding one but am on the fence. I do have 4:10s, stainless works headers and corsa exhaust. I would think these 3 should help if I go with the flywheel. Thanks Jim

Jim,
Don't know where you are located but I have stock dual mass flywheel, 4:10's, top end porting and chip/tune by Haibeck, Stainless works headers with high flow cats and Corsa. If you are in the MD area you can take my 92 out for a spin and see what you think. Like others have said, some lightweight flywheels rattle like rocks in a can and some do not. I did not want to take the chance of rocks in a can and mine is plenty fast for me...scares me at times!

[Hib Halverson]

It's not the aluminum flywheels that rattle.

It's the transmission. The correct nomenclature is "gear rattle". It happens at idle and at very low engine speeds under light load. It occurs because, at idle and low engine speeds and only four firing impulses per revolution, engine speed actually fluctuates enough at a low frequency that the main drive gear and the counter gear start "rattling" because of the clearance between the teeth.

In the manual transmission nomenclature, "center distance" is the distance between the centerline of the drive gears and the centerline of the countershaft. The greater the center distance, the more pronounced the gear rattle will be. During early development of the S6-40, it was quickly obvious that gear-rattle was a problem.

The dual-mass flywheel designed for the first LT5?one of the first applications of that technology in a light vehicle?was a partial solution to gear rattle. The flywheel had a spring damped secondary mass the purpose of which was to "smooth out" the torque fluctuations caused by firing impulses at idle RPM.

Install an aluminum flywheel, which is a standard or "single mass" wheel, and you eliminate the gear rattle mitigating the function of the dual mass wheel. With an early-style, 610-Nm transmission, the increase in rattle is very noticeable. With a late-style, 540-Nm transmission, the increase is noticeable but not so bad.

As I was not a drag racer and liked the quicker engine acceleration which comes with an aluminum flywheel, I installed a McLeod aluminum wheel in Barney, my dear-departed '95 SN 140. There was an increase in rattle, but I cut that about in half by installing higher output ignition coils, then opening up the plug gaps by .010 or so and going to Red Line Lightweight Shockproof Gear Oil which used a calcium-based EP additive package that has a cushioning effect between gear teeth.

Those solutions would still be valid, today.