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.

[Paul Workman]

I've got the 13# Fidanza Al in my 500+ HP car with stock 345s and Ami has (I believe) one in her 500+HP Z w/ 410s.

My cams are stock and the idle is set @~900 and I have NO rattle to speak of.

Ami's car has an AL flywheel & Pete's cams (and mild porting) and it rattles some.

Both cars are perfectly streetable to the point of not ever giving it a second thought in normal driving.

The PHYSICS favors the lighter FW when RPM is changing: the faster the change in RPM, the less energy is absorbed and that power goes to the rear wheels. That equated to very noticeable increase in the "snap" felt in the seat of the pants, especially in the lowest two gears! In fact, the rear end often breaks loose in first gear with only the accelerator on my car (with the stock 345 diff @ that!)

Some prefer the stock FW, especially for drag racing. A lot of energy can be stored in the FW at launch which can be beneficial as the clutch is released. However, the dyno graphs tell the story when it comes to putting it on the ground: it costs as much as 15-20 HP in 4th gear (on a 500+ HP 350 cid LT5), AND A WHALE OF A LOT MORE in 1st, 2nd, & 3rd! (as the CHANGE in rpm is higher in the lower gears - especially noticeable in FIRST!)

It only took me a single outing to become accustomed to the different feel (and there is some). But, after that I never give it a second thought in the ?10 years and 30k miles of spirited driving!

So, is it worth all the hoopalah? Some say yes, others say no. It depends a lot on your preferred driving style - what you like. My favorite is mountain twisties or the track where much of it is in 2nd and 3rd gear (especially in the mountains). I really like the snap the Al FW provides when coming out of a corner. I can only imagine how much more it feels like having 410s IF the gear changing doesn't get too annoying; someday I'll get to try the wife's car in the twisties with her 410s & comparable HP.

Bottom line? For normal or stop and go driving, it will only take a few minutes and you'll be accustomed to the difference. After that, and I doubt you'd ever give it another thought. But, you'll notice the extra "snap" in the twisties...for a while...and then you become accustomed to it and never think about it UNTIL you jump into a car with the stock FW. SLUGGISH, at first.

I like my aluminum FW and would not go back to stock. I like the quick RPM response "seat of the pants" feel, primarily whenever the lower gears are involved along with WOT. For normal driving - especially if (Pete)s cams are involved, maybe, MAYBE the stock FW is the choice.

But, hey! You needn't go to one extreme or the other. There ARE choices in between the 13# Fidanza and the 43# stock dual mass - such as the 18-25# single mass FWs some prefer. Just sayin...

[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!