Currently using an 11" Centerforce DF behind a 470 with an 18 spline. Street driven, E-body, 3450 lbs., 4:10 / 3:55 with 9" x 28" slicks. Still holding strong after 12+ years of casual street driving and 50-60, test and tune, quarter mile runs on it. I have used Borg and Beck style clutches in the past. However, this is my first diaphragm type setup. Recently read about a "Clutchtamer" device which has peaked my interest. Seems like several clutch manufactures offer quality options.