I would use the Dart Platinumn Pro-1 325. Without a lot of work, they can flow 390+ on the intake. Over 400 isn't very hard either, with a 2.3 intake. And the port is still smallish, and 335cc, or a touch bigger. With those heads, on a 502, is this a 502, or is it going to be a 509? I have a 509 combo, with the above heads, and what i consider a mild cam, 13.5:1 compression, that makes 830hp. I did one 509 a few years back, as a revised combo of the above, that made almost 900hp. That one was a bit more high strung, and had a fairly serious cam. In a 2750lb 68 camaro drag car, it went 5.32 at almost 130 in the 1/8th, and 8.40 at 157mph in the 1/4, so the potential is there.
Frank
Advanced Performance
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