Zboy325

I recently installed a spec stage 1 clutch and a fidanza aluminum flywheel in my 95 Z28. i installed the parts originally without balancing the flywheel to the new pressure plate which lead to series of unfortunate events. Anyway, i sent both the clutch and flywheel back to Spec and they say they balanced the fidanza flywheel to the new clutch. After the second install, the car seems to be running fine excpet for chatter (which should get better with break in right?), and a slight vibration felt on the clutch pedal when not depressed to the floor (engaged). im unsure if spec did a crapy balancing job, or if the lighter weight parts are not dampening normal engine vibrations which could not be felt with the heavier, stock flywheel. Anyone experience the same results with an aluminum flywheel?? Thanks!!

blackztpi

two things. 1 being that the flhywheel must match the rotating assembly because lt1's are externally balanced. the second is the aluminum flywheel. An aluminum flywheel is nice on a 4 banger, but a v8 had enough ball to get the flywheel spinning quickly as it is. keep in mind, the heavier the flywheel the harder it is to slow that motor down once it's going. basically, it wont lose rpm as fast as a lighter flywheel. you are losing some of the dampening affect as well. just hope the flywheel matches your rotating assembly or else you'll go through main bearings eventually.

med_reject

your fidanza flywheel must be balanced to a stock flywheel or you will kill your bearings. That means you give a machine shop a stock flywheel and your fidanza. The stock has a counterweight on it to externally balance the lt1 motor. The fidanza is neutrally balanced and will work fine on an internally balanced motor (eg, typicall 383 or 355).