1971 Duster 360/727

Yea man! Looks good. .030 for an overbore is ok and fine. Which speed pro Pistons did you get? I just did there hyper-U slugs.

Also, the "J" heads are basically the same as the X heads only with normally seen smaller valves. They will port out very well. There should be no problem making power with the J heads. I have run in the 12's with stock J heads. It takes a good bit of a heavier cam and more gear to do so verse a ported head. But it is cheaper.
(Oh! Camaro seats look really good.)