I'm running a 460 hp ATK 6.0 that I've added a supercharger to, probably well over 600 hp at crank. Truck runs 13s, including this week at Indy Hot Rod Power Tour stop. I've got the 10 bolt with a TrueTrac and love it. The only issue I have is keeping the diff cover sealed. 7 of the 10 bolts are Stage 8 locking bolts but driving home from Indy this week noticed gear lube on back of truck. Gasket failed on top side of cover, two of the non-Stage 8 bolts I removed without using any tools. I put in those Stage 8s several years ago when I couldn't keep the cover sealed for more than a few months and it's been trouble free until now. Should be able to see broken ends of the gasket in the pic.