Motor is a 502 with Dart Pro 1 aluminum heads, 119cc chambers and 310cc intake runners. Estimate compression in the low 9:1 range. Cam is Comp Cams extreme marine hydraulic roller with about 580 lift and 240 @ 50 duration. Recently switched to the Dart heads from the stock GM cast irons but did not change the cam. Other details are Vic Jr. single stage alum intake, Holley 850 w/ vacuum secondaries and EMI Thunder exhaust.
Need to have shop pull engine and jet intake due to broken bolt and water leak on intake. While the motor is out, WTF? Estimate current HP is about 420 (5,200 RPMs w/ Mag./Bronze A/B cut, Berkeley). Boat (20' Caribbean) and motor runs real good now, but I know the motor is not optimized for the new heads. Thinking about new cam (maybe something in the 640 lift range) and bumping the compression (due to the aluminum heads). I know the first general order is to have the heads flowed for data, but these are rather popular heads, so isn't flow data readily available?
Looking for advice on proper cam selection (lake application, need to idle in no wake zones) and proper compression (mill the heads?). Will this yield about 500 HP, or a bump of about 70 - 80 HP? If not, probably not worth the trouble.