E-street vs Promaxx vs 440 Source

And this is exactly why I mentioned the stroker kit... If he had that much displacement he could probably get away with the heads that he has no problem and have a great foundation...
But this is a how do I get there on heads thread...
My buddy's 543 made 525hp/620lb-ft with stock unported 906 heads with a 240ish 540lift cam, he's ordering 270's so it should increase substantially.