[Janih]

Has anyone ever measured the stock gm oval port heads True intake cross sectional area? Is It really that big that is advertised.

 

[68Chevele]

Mt 781's before porting were 255cc's the biggest ovals I cc'ed were the 290 castings that cam in at 265 to 267cc's and I thing they were closed chambered heads. Maybe Mark will chime in on the csa.

 

[steelcomp]

Pretty sure they're a little under 3 sq in at the minimum which is just past the pushrod.