Lets talk gears !

Hey yall broke my pig last night at test/tune. What gear would yall think for street/strip [bracket] racin . It now has 5.13 35 spline strange axles 345cu ,m1 dp750,557mpsolid cam,hookerheaders,weighs3317w/ me been shifting at 6500 conservatively ,runs 7.78 reg. 1/8 mile.I was considering 4.30 cause i like to drive to town monthly but i know you cannot have it all any suggestions would bee very help ful . :-D
I am surprised that an 8 3/4 broke behind a small block. Are you running slicks and a trans brake? What broke in the rear. The reason I'm asking is to try to make my 5.13 bullet-proof.