Originally posted by 76GMC1500
Oh, the head don't have oversized runners if they don't have the X at the end of the casting number.
Hmmm... may explain why my 487X heads did fairly well with my combo. I have a 9.8:1 350 +.040, an Edelbrock Performer EPS manifold with a Comp Cams 268H cam pushing 1.6:1 roller rockers and a Hollley 600 double-pumper.

Any idea what runner size this head has? How much bigger is it than the 487? I found on mortec that they have a 75cc chamber. The more I read about the other intricacies, the more I want to know.

Thanks.