What all of us should have asked is what is your definition of a 'mild blown street motor' - and what car, what trans, what gearing, etc? What are the specs you're thinking of for the engine?
Bore / Stroke / Cubic Inches
Porting and Relieving - none, or to what level
Valves - sizes
Heads / Chambers / Compression Ratio
Ignition
Blower / Overdrive / Boost
Fuel system - type, number of carbs (if carbs), approximate CFM
Flywheel / Clutch
Tranmission, Gearing
What characteristics are you looking for in the engine? How will you be driving it and what are your overall goals?
I think myself and others 'shot the gun a bit' - we were off the diving board and into the pool without knowing much. My bad!
B&S