Has anyone had experience with steel vs aluminum flywheels? I just upgraded my 2011 motor (ford racing 5L) and had a new spec clutch installed. Just got it yesterday from the shop. I noticed a lot of clutch chatter in first, and in 4th gear at about 1300 rpm, the vibration noise is for lack of a better word, undesirable upon acceleration. My stock single disc clutch had a steel flywheel and never had this issue. Since I'm new to this clutch, thought I'd see if anyone had a similar issue. I'm about ready to take the spec dual disc clutch back out and put my old stock back in. Any thoughts?