Drag Racing With Clutch Type Sure-grip

413 said
I have a 3700lb car I drag race with slicks and a 3.91 clutch SG. What always happens is the spider gears or ring gear break around 400 runs. (4 times now) The SG always spins both tires just fine. I don’t think it’s hard on the clutches going in a straight line.

I have a 742 case 3.91 clutch sure grip, factory carrier. Can you tell me where you are Getting the spiders.
Both SGBARRACCUDA and I looked hi and low for them, had to buy used
FYI, Dr Diff has Dana clutches that will work in 8 3/4 with slight modifications.