Engine A Little Help Please.

If i remember correctly the 255 is a small bore 302 heads and intake has oval passages rather then rectangular ports. Best thing I can suggest is getting the heads and intake off of a later model 302 and going that route. Only thing is that im not sure if the valves will clear the cylinder bore or the pistons.. you would really have to tear it down and test fit everything. As far as im aware the block is the same otherwise.

Too bad they didn't make that block out of aluminum. Buick used to make a aluminum 215 cu in engine. Olds threw different heads and a turbo on it. 215 HP and 300 ft lbs of torque.