Hey guys, I was wondering if anyone is running or has friend that is running an aluminum flywheel on there 6 speed vette. I have a 2001 Z06 with heads, cam headers. Just curious what the benefits and most importantly downfalls would be to going aluminum. Thanks.

 

I know this was not a vette but I thought I would tell you what I learned on a 200sx SER. I got a faster reving engine that felt great. On the negative it took alot of life out of the clutch getting used to it's new engagment, and on a lesser note it's impossible to pop the clutch with a dead battery. I really liked the response of the throttle after putting it on so I was more happy than aggravated.
Hope this helps.
Sam

 

It will need more throttle from a dead stop to get going. If you have an aggressive clutch, it will be even worse. It will rev faster and will show more power on the dyno because the motor will spin up faster. I found the Textralia Billet steel flywheel to be a good compromise.

 

I've had a Luk stage II w/ the fidanza aluminum flywheel since '05. I have 80k on my car now. Clutch is going strong and car revs wonderfully.

Not sure why people say you have to slip the clutch more... you don't... most just keep on spreading the same internet rumors.

 

I didn't state "slip more" I stated "more throttle", there's a difference. Not internet rumor, have driven aluminum flywheels and they just don't drive the same on the street.

 

I agree with Bob, there is the need for more throttle, if you slip the clutch you will wear it out quicker. I did that learning low speed manuevers, My fault not the flywheels'. But once you learn it it is well worth it.

 

I've been driving w/ the Fidanza for over 2 years and 30,000+ miles. I've driven my father's '04 Z and my mother's '99 vert back to back to back... not drastic difference.

 

Next someones gonna say they are not good for drag racing. Another internet rumor that people have no clue about but just pass on false info.

 

I had the SPEC Stage III Clutch package installed. I also install the SPEC Aluminum flywheel. The pressure plate was aluminum also.

I didn't like the Stage III clutch disc for street driving, too much chatter on slow take off. Once engaged is was great. I replaced the Stage III clutch disc with a Stage I disc and all is good in Rivercity. Starting from a standstill doesn't require any different driving than before. Remember I put in an aluminum pressure plate also. The total weight savings was about 23 lbs.

I had an aluminum flywheel in a '64 327/300 HP Vette back in the 60's. I loved the quick revs and quicker acceleration of the motor with the light wheel.

I notice quicker acceleration with the light wheel in the LS1 motor but the free rev of the LS1 is not like an old 327 small block. The newer motor just doesn't rev as quick like the old one so the difference of the ligher wheel isn't that noticeable on free revs.

Now, when I accelerate I feel the difference in how fast the motor gets to redline now versus with the heavier wheel and pressure plate.

THIS IS ALL SEAT OF THE PANTS FEEL! No hard track times or anything else to substantiate these statements.

Hope this helps. JD

 

Here is an article where they showed the difference on a dyno. The Fidanza/Spec revs much faster than the stock flywheel.

Fidanza Dyno

I think the other observation is that the LS7 clutch setup softens the response and some guys have complained the car doesn't rev as well. I avoided this setup for that very reason and it will show a loss on the dyno as well. Its great for driving in traffic with the heavy setup (about 10 lbs more than the stock Z06 setup). I went back and forth on this prior to installing my clutch and in the end went part way towards aluminum (billet steel is 18 lbs whereas the stock flywheel is about 24 lbs). The LS7 clutch with the LS2 Fidanza aluminum flywheel was actually heavier still than the Textralia. The other point worth noting is that weight is not what controls the flywheel acceleration, its the rotary inertia of the entire setup.

 

I had an aluminum flywheel with a Spec clutch....hated it....chattered ALOT. I went to the Exedy Twin with a lightened steel flywheel...... chatter is gone..... IMO the little you gain from an aluminum flywheel isn't worth the the fussy clutch pedal.

 

Everything I hear says spec clutch suck in general... I've been driving w/ an aluminum flywheel for almost 3 years now w/o issue. Many HPDEs... many street miles. It's fine!

 

Im not sure if people are saying that a lightweight flywheel is not good for drag racing or if they are saying it is not good for durability in drag race conditions.

A lightweight flywheel is easier to rev no doubt about that. Fun for the road race guys especially when matching revs during shifts.

For the street though you have to give it more gas then a steel flywheel - this only makes sense. The lightweight is not storing as much energy as the steel thus when the clutch comes out there is less energy transferred to the wheels.

The way people drive will determine if this is a factor though. When I first got my lightweight clutch I had a hard time with it. Now it is second nature and I probably give more gas to cars that do not have it so I dont notice a difference.

An all out drag car though would probably not have to worry as much about the flywheel. They set at 6K rpms and launch. Power is coming to the ground no matter what. After launch the flywheel is added weight so lightweight would make sense.

Even if the differneces are small I personally do not see an advantage of a street car with the aluminum flywheel. The lightweight steel that have come out are good for the street. For the track you have to look at your complete setup and make a decision what will work the best with that setup.

Maybe this is one of those debates like RamAir

 

Lightening the flywheel assembly with a lightweight steel or better yet aluminum piece is a good move. Provides improved throttle response and engine acceleration, and better numbers on an inertia style chassis dyno. Even with a 15lb aluminum version, the total assembly weight (pressure plate, clutch, and flywheel) is still plenty to offer enough inertia to get the car moving. Trying to accelerate more weight than you need to accomplish that task is simply a waste of engine torque (and power). Diameter plays an important role in here as well, but if we are discussing standard diameter single disc type clutch assemblies, even with an aluminum wheel the total weight of the package is usually close to or slightly more than 40 lbs....more than enough to get the job done.

I would never drive a performance vehicle with a lazy heavy flywheel assembly....especially one Im modifying to improve its power output, its simply counterproductive. As soon as I started modding my Vette I swapped my stocker for an aluminum wheel with a Spec II clutch at the time....noticable difference....I loved it.

Get the lighter wheel....it offers nothing but upsides and could help to reduce shifter vibration if the balance is better than the heavy factory piece you will be replacing.

Let us know if you take the plunge and how you like it....you wont be sorry you did.

Tony

 

Ooooo, I like these kinds of discussions.

For drag racing, heavier flywheels generally work best with lower powered cars. The name of the game is inertia. The idea is to get the car moving while slightly slipping the tires until the engine is up to an appropriate rpm. Then, the tires grip and the car goes. Otherwise, the car will bog as soon as the the car hooks up, assuming it doesn't get to the right rpm. On higher horsepower cars, the extra weight is not needed. They will have enough power to spin the tires without the added inertia of a heavier flywheel. There are other considerations. For instance, a car can have very high horsepower, but it happens at high rpm and may be low on torque. Those cars may also benefit from use of a heavier flywheel.

Other uses for heavier flywheels are smoother engagement of the clutch and making an engine feel smoother. The engagement thing is pretty obvious. The smooth thing is most noticeable with fewer cylinders. It helps to dampen power pulses from individual cylinders firing.

As long as there is adequate power available, I can't really think of a reason to not use a lightweight flywheel. With a vette, there seems to be plenty of power to accellerate. The engine also seems to be plenty smooth enough to not need a lot of dampening. Accelleration should also improve since there is less mass to get moving.

I can't remember the numbers but there used to be a rule of thumb that went something like: every pound of rotating mass = 100 pounds of vehicle weight. (don't use this as a quote, but you get the picture)

Having said all this, the only car I've ever had with a light flywheel was a Datsun 260/280Z (260Z with a modified 280Z engine). I can't remember the details, but I think the stock cast iron flywheel was something like 45 lbs. I put in an 11 lb aluminum flywheel with a light weight centerforce clutch. Daily driving was really no different. Drag race style accellerating from a dead stop was tricky at best. Accellerating from a roll was fun. Much quicker.

YMMV

 

Hey guys, thanks for all your imput.. Gripforce sells a Fidenza aluminum flywheel for $275 shipped so I bought one. Should be installed on Tuesday I wasnt sure the best clutch to go with I suppose I should of asked about that too. I bought a centerforce from summit.. Is that gona be worth a crap? I paid $389 for that clutch let me know about the clutch.. Thanks alot.

 

I had the same setup and same experience. However the chatter went away after break-in (it took a while). I also had this done along with a 4.10 gear. I now need a head and cam package with higher redline. I'm on the rev limiter so quick that it still catches me off gaurd.

 

 

To add to the confusion, I run a RAM Dual Disk clutch with an aluminum flywheel on my 403. The combined weight on the clutch flywheel assembly is 8lbs less than the LS6 clutch and flywheel and a whole lot lighter than the LS7 clutch assembly. I don't see any downside. May be different if I ran a single disk clutch setup with the aluminum flywheel.

 

to me it was very simple

aluminum flywheel will let the engine rev up quicker BUT it will also fall quicker than steel. therefore for drag racing i think steel is good, only way on a drag strip with an aluminum flywheel is to power shift and never let of the gas,

that is if we still talking about it?