I have the stage 1 heads. I never asked what the difference was. I spent the extra $360 dollars on modmax valves instead of stage 2 heads for $300 extra. I figured since my heads came off my car and they are already being ported, why not upgrade my valves while they have them.
Stge II is better flow numbers. If you want ported heads Fox Lake is a good choice. Ron over there took care of me. I would keep my eye on the classifieds section people sell these every now and then you could pick them up cheap.
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