318 head porting for the average joe

Wild and crazy guy says...'' go flat ''...

318 Head Porting exhaust.JPG

150 cfm's, same as a 340/360 stock port!

Coolio, with a 1.500 valve...

318 Head Porting ehaust seat.JPG

I'm gonna go with a 1.550 as I have hardened seats already fitted lol...

200cfm's in, 150 cfm's out, PERFECTO...