The 1.08, with the mods you are contemplating, is perfect. Going to a 1.12 will reduce the throttle response. I oughta know - went down that path myself. My engine is a 331, Boss 302 cam, ported with larger valves. Stock intake and a 1.08 with 58 primary, 67 secondary. Never pulled more than 430cfm on the dyno, within the range of the 1.08. Good luck!
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