Clutch technologies have certainly improved. I'm running Centerforce 11" diaphragm. This is the first diaphragm style clutch I have used since the 70s and a stock diaphragm in my GTO that I would described less than stellar. The car was purchased with that Centerforce recently installed. I took a peek at one. And it's night to day difference than past. Clutch discussions is a whole other subject matter. But because the pressure plate is 11" vs 10.4" I knew what was suspected before actually viewing. An 18 spline A833.