Here's a couple of photos of the intake port on the stock GMC 302 head. This is a cross section view and is an actual 302 head that was sliced with a band saw through the intake and exhaust ports giving a nice view. Many wonder what these things are really like inside so here's a shot of inside of an actual 302 head. You can all thank Arlyn Unrein of Russell, KS who had the wherewithall to slice up a scrap 302 head and send it to me all painted up so we can actually see what's inside this sucker!
Here's another view of it:
This gives you a sense of just what the inside of these heads really looks like!
