If using the 302 8.200" block as a basis use the 3.25" stroke /5.4" rod combo if you want to run up round 7000 plus with solid cam. If your going to run a hydraulic cam then you could try the 3.40" stroke/5.40" rod deal-not my favorite though.
A plain 3.00" stroke/5.625" rod/1.070" piston would sound grouse at 8000, valve train would cost $$$!
Jac Mac