I dunno. I was thinkin with iron heads, 476 was purdy dang good. That's 101 more than a HP 440. I figure 20-35 HP for the headers, maybe 15 for the rockers, 15 or 30 for the good intake and big carb and another 20 maybe for the hot ignition. Plus whatever cam he's got in it. Some people just don't want a pro stock engine to drive around all the time. (see me raisin my hand here) Seems right on track to me. Are you addin in some for the purdy air cleaner and valve covers? I went to high school with a guy like that. He honestly thought chrome valve covers were an easy 20 HP. No, I'm serious.