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Completed 7/17/2002

A lightweight flywheel reduces rotational driveline mass. Less rotational driveline mass means more torque gets delivered to your wheels. The UUC Lightweight flywheel weighs in at 13.4 pounds. The stock LuK dual-mass flywheel is about 24 pounds. For each pound of rotational mass you remove from your drivetrain, it is the same as removing about (7) seven times that in vehicle weight. So, for example, the UUC lightweight flywheel will remove about 10 pounds of rotational mass. My car will perform like it is about 70 pounds lighter in weight.

What this means is better acceleration and quicker engine response. The downsides to a lighter flywheel are possible audible idle chatter (where the pulses of the ignition cycle are no longer absorbed by a heavy flywheel and can be heard in the transmission at idle) and it takes some time getting used to driving with one. A lighter flywheel will make the engine easier to stall when starting from a stop and your shifts will need to be faster as the RPMs will drop much faster when you push the clutch in and let off the gas.

1 - UUC Lightweight Flywheel
     (UUC MOTORWERKS $499 part #LFWLE46)

See below...

This is simply *not* a DIY kind of job. My dealer owed me a new clutch based on an active TSB (Technical Service Bulletin), and I got it installed at that time.

I looked into doing this modification myself, but it involves removing the driveline, exhaust, and transmission. And, to get to a few of the transmission bell housing bolts, you have to unbolt the engine and rock it back on the mounts. This is something I do not have the equipment to support, so I was lucky enough to time this install with my clutch replacement.

IMPORTANT NOTE: If you have a 323/325, you will need to use the clutch and throwout bearing from a 328/330 with this flywheel. The 323/325 and 328/330 have different sized clutch plates in them. It is also recommended to pick up a new set of (8) eight flywheel bolts. These are shear bolts and the old ones should not be reused.



Talk about impressive! The engine feels like it has been set free. It revs so easily and is much more responsive. No more hesitation in the acclerator pedal. This thing just wants to get up and haul ass!

Acceleration feels much improved especially in the early gears, but the difference can be felt in every gear. The RPM redline is acheived much faster with seemingly nothing standing in the engine's way.

Shifting took a few miles to perfect, but it is absolutely incredible now. I used to out-shift the engine/tranny before; the RPMs never dropped enough to put me into my next torque "sweet spot". Now, my shifting speed is matched by the change in engine speed almost as if by design. Even my short shift kit seems smoother.

Idle chatter is barely noticable inside the car. If you even have the A/C fan on, you won't notice it. If you use your radio every day (like me), you will forget about any chatter in no time. Outside the car, the chatter is more noticable. I would say it about doubles the volume of your engine. I only got chatter when in neutral and my foot off the clutch. Since 99% of my driving involves NOT being in neutral, the performance gain far outweighs the noise issue.

SOON TO COME: I will be doing a short video of the tach before and after to show the difference in engine response and the idle chatter inside and out.

  © MarvelPhx