[mrmark1957]

I need advise from the experienced gurus here. I picked up a '73 Lemans with a fresh rebuilt .030 over 400 motor. Has Silvo-lite 1526 pistons ( -10.0cc) and probably .020 down in the block, 6X-8 heads. 204/214 Summit 2800 cam, Fel-pro gaskets and ARP rod bolts. Quadrajet, stock intake, logs, 2" stock exhaust. 3.23 gears, stock 400 Turbo and converter. Engine runs nice but doesn't have much power. I have access to a freshly rebuilt pair of big valve # 13 heads (checked at 73.5 cc). Can I bolt these on with a little more cam ( a Summit 2801 or 2802 or an 068 ) and run this on pump gas on the street ? Or will compression be too high / quench too big and have detonation / pinging ? I would like to give this car some go with a simple head and cam swap. TIA !