331/347

Asking for imputs, if I'm wanting to runlow to mid 12's,how much hp would I need in a 67 fastback? I'm guessing around 425 to the rear. I have decided to go with an EFI 5.0(hood issues). My question is this, should I build a strong 331 or 347 and hope I hit my mark? Or, should I upgrade a stock 5.0 to handle a supercharger. Lastly, should I build a 331 and supercharge it? I'm either going with 5 or 6 spd, and have 3:55 gears. It will see some track use, but I just want a clean reliable sleeper that can get most of the power to the wheels. Thanks

I would build a mild 306 with a good set of heads,intake,a good custom cam and the supercharger should give you the power you want.
[addsig]