what kinda heads would you put on a 318 if you were goin with a 509/292 cam and flat top pistons. ive heard alot of good things about 360 heads. what casting number 360 heads and if u went with a 318/340 head what would be the best one. mine are 4027598. 1.88/1.60 valves. 65 to 71.5 cc heads. idk what they are yet. im thinking of milling down a set of 360 heads and puttin m on. but im also thinkin of just port polishing the 318 heads i have. milling them down too.