JDSfastGN,
I was running mid to high 10's when I started breaking axles.
Approx 1.36 - 1.49 60' times.
On 28 x 10.5w Slicks using a trans brake.
At minimum, I would go back with a quality (rebuildable) posi, new gears, new bearings & a T/A cover.
I've heard of people going really fast with a well set up 8.5 rearend.
You might call EJ and find out who built his rearend. His has held up very well to his high HP engine, plus EJ makes sure his rearend is warmed up before you hit it hard off the line, make one real easy pass before you shock the drive train with a hard launch.
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