Yes. That probably is part of the problem. First I bought an dual-disc RPS clutch with a steel flywheel, but when it arrived it didn't fit. The mechanic them ordered a dual-disc clutch from SPEC; unknown to me it shipped with an aluminum flywheel. After the mechanic installed it, I looked at the assembly and found that it too didn't fit well, as the bolts to the clutch were sticking out so as to prevent the cover from fitting properly. He had put washers on so the cover plate could be attached. Anyway, I drove it and have a vibration and like a buzzing noise which occurs under load - specifically in 3rd thru 5 the gear all around the 1,200 to 1,600 rpm range. I thought it might have been the plate, not being attached well, was vibrating, but another person said the flywheel may not have been balanced. Since it is aluminum (which I have had no previous experience with and didn't know till after it was installed it was put in) when I push the clutch in after starting their is a sandpaper like sound. This whole thing is bugging me as I paid about $1,300 or so for the clutch assembly not including labor for installation. I am thinking of just putting my stock clutch back in. Don't think the distributor will do anything for me.