bri

iTrader: (2)

i think i saw an FHI 'STi' lightened flywheel. anyone have info on that i.e. not as prone to deny warranty coverage

Kevin M

iTrader: (12)

I don't know the exact weight, but on a hunch I would guess that it's about 14 pounds (Exedy, supplier of the OEM clutches and flywheels for Subaru, makes a 14 pound STi flywheel). It's still not covered under warranty however- no STi/SPT parts are.

Maniac

iTrader: (6)

STI Flywheel is 18lbs...

Kevin M

iTrader: (12)

Is that the standard factory one or the aftermarket one?

Maniac

iTrader: (6)

Sorry, the factory STI flywheel is 18lbs... It is a significant improvement from the approx 24-26lbs factory WRX flywheel.

Again, as I said before, 14lbs is the LIGHTEST I'd go on a street car for driveability's sake!

Wingless Wonder

iTrader: (7)

If I were replacing the clutch or tranny, I'd consider a lighter than stock flywheel. I don't think it's cost effective since the weight savings is only part of the rotational mass on a car. Going to lighter wheels would also improve acceleration and reduce unsprung weight at the same time for better handling.

Free-revving in neutral due to a lighter weight flywheel doesn't correspond proportionally to quicker vehicle acceleration. Think about it - you've removed 10 to 14 pounds of weight from the vehicle but the engine still has to apply power to accelerate another 3000 pounds!

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0==WW==0
"…axles of evil…" - george w. bush

Kevin M

iTrader: (12)

It's true that the lightweight flywheel does little as far as improving overall acceleration. But it works wonders for making the car easier and more rewarding to drive. Rev-matching becomes much faster and easier, upshifts get smoother, and you can shift a little faster with no additional stress on your synchros. While doing the flywheel by itself, just to do it, is not very cost effective, the added cost during an already necessary clutch replacement is an excellent value. I wholeheartedly recommend this mod to those who drive their cars hard on a regular basis.
Also Alan, remember that the lighter weight benefits of the flywheel are similar to those of wheels. Rotational inertia is a greater factor than actual inertia. Dave Coleman had a great write-up about it in Technobabble a while back (unless it was in the suck-squish-bang-blow series). It's a good read and explains why a 50% reduction in rotating mass results in much more than 50% performance improvement.

DJTEN4

iTrader: (4)

i have the fidanza lightened flywheel, its 9.5 pounds. i didnt get any cel's, but now that i have done my headers, i am... can anyone explain to me why i get cel's with the flywheel. i dont see the connection.
btw, im getting the utec this week, will that stop the cel's from coming? i sure as hell hope so.
when i got my cel checked it was misfires like you said...
i have got perrin cold air, lightened pully, borla headers, helix up/down, greddy cat back, and the flywheel. i dont know why im getting these, any help...?