Here's the scripture off of SPMotorsports site for the drive axles...
STAGE 1
1117 billet inner housing with oversized Tripod, 4130 chrome-moly induction hardened bar, 1117 billet outer C.V. induction hardened, Thermoplastic Elastomer Duraboot spline plug inner C.V. design. Stage 1 NOT recommend for drag racing.
STAGE 2
1117 billet inner housing oversized tripod, race-proven chrome-moly 4340 torsional center, 4340 c-m outer C.V. induction hardened, Thermoplastic Elastomer Duraboot spline plug inner C.V. design.
Just thought i'd try and help out.
Robert
