A 8.25 rear end will last for long time with up to 300 rear wheel horsepower The torque of the 493 you have will kill it in short order if running slicks or 11.5 inch drag TA's like I did but up until then I had close o 800 runs including two trans explosions that took out trans and drive shaft split in two my 8.25 survived all that and broke the spider gears Open rear end Fixed it in parking lot and drove it home