Your car will be no faster with the heads then with a standard set of 1.88 360 heads but use what you have on hand. Problem is that engine has no real comp . You would be better off with standard comp 260 Hyd in fact it will run better. Get a mech advance dist and get as much total in it as you can at least 44 degree's by 2000 it will really pickup go with a 600 dbl pumper and a 4 hole 1 inch spacer on the LD DO NOT close off heat passage and run a 195 stat 180 dead of summer. If you have the money gear it to at least 3.23s as you only have 5500 rpm tops power is done in low 5k renge
I went through a similar situation only it was Camaro Z28 that was 305 smog motor powered. It was one of the ones that did not have an LT1 motor that was using the big valve heads. The owner overheated the motor and both heads cracked. He got a deal (??) on some big valve heads and when we compared the new heads to the old, I showed him that the big valve, big chamber heads were not compatible with the dished 305 pistons because the CR would be far less than stock and the result would be an embarrassing dog. I put the right heads for the application on the motor and never heard from the fool again.
