340 Build

I wouldn't build to some vague power level for a street car, I'd Start with where you want the powerband to be idle-5500,1000-6000,1500-6500,2000-7000 etc... And pick a cam for that powerband and that will pretty much dictate which gear ratio, compression, intake, stall speed, carb and heads your combo will need. If you need more power than your engine can produce in the powerband that's usefull to you than you need a bigger engine.