I ran a RAM clutch in my 68 Coronet, mild 318 with 3:91 gears, it lasted 6 weeks, then I stuck in a zoom, it lasted 41/2 weeks, spent the money and installed a center force, it's still in there and it's been there in there sence 1997. When I built the 535 for my 70 GTX 2 years ago I installed a center force, it lasted 3 days, then I made it cost me and installed a McLoed duel disk, no more clutch problems. The Mcloed see's 900 horse on a regular basis.