I know that an aluminum flywheel will allow the engine to rev quicker. What about torque? I've heard that low end torque suffers. Those of you with these flywheels , how do they perform on the street?
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Hi,
There is less mass to rotate with an aluminium flywheel. The big diameter of the flywheel strengthens this effect. When you push the throttle, with a heavy flywheel, it takes longer time for the engine to gain rpm. The energy used during "rev-up-time" is then stored in the flywheel. And may be used as "extra" torque to launch the car. But as soon as the car has left the line and the car hooks-up, a LIGHT flywheel is to prefer.
Now, the Pantera is a sportscar, and benefit the most from a LIGHT flywheel. That creates a nice road driving response. The ZF is not very impressed by the "heavy flywheel 7000 rpm" starts anyway. You do NOT suffer engine torque. But you may notice a slight more nervous idle, and use a little more clutch.
Goran M
There is less mass to rotate with an aluminium flywheel. The big diameter of the flywheel strengthens this effect. When you push the throttle, with a heavy flywheel, it takes longer time for the engine to gain rpm. The energy used during "rev-up-time" is then stored in the flywheel. And may be used as "extra" torque to launch the car. But as soon as the car has left the line and the car hooks-up, a LIGHT flywheel is to prefer.
Now, the Pantera is a sportscar, and benefit the most from a LIGHT flywheel. That creates a nice road driving response. The ZF is not very impressed by the "heavy flywheel 7000 rpm" starts anyway. You do NOT suffer engine torque. But you may notice a slight more nervous idle, and use a little more clutch.
Goran M
Besides what Goran says, be aware that all alloy flywheels that I've seen have much thicker flywheel flanges where they bolt onto the crankshaft, due to the lower tensile strength of aluminum. So the working face of the clutch is moved back towards the transaxle significantly. This means a complete readjustment of your clutch linkage- probably including shifting the bellcrank on the splined cross-shaft a couple of splines. On some cars, the bellcrank end will touch the bellhousing when this is done, so some grinding on the bellhousing might be necessary. If the flywheel flange is thick enough, you may also need longer flywheel bolts.... and flywheel bolts are made with special short heads. This sometimes isn't quite a bolt-on mod!
What about flywheels that are lighter than stock and will fit without modifications? Also, the aluminum or any other flywheel should be able to bolt on with out rebalncing the motor, correct? Any vendors reading this that have a aluminum or lighter than stock flywheel that bolts on without mods?