I'd email INTENSE, but thought I'd post in the event anyone else is wondering.

What are the differences between the stage 2 and stage 3 cam+head packages from INTENSE?

So someone gets the stage 2 or stage 3 package, Obviously they are going to need headers, bigger injectors, but what else is a supporting mod for one of these?

Why are the Stage 3 heads $400 more than the stage 2?

With a Gen 3 M90, what sort of WHP would one see with one of these? Gen-V or IC would be out of the question for an argument sake.

While I'd like to help out and answer those questions, I can't think of anyone that can answer them better than INTENSE. They will have all the data and HP numbers you are looking to learn.

The stage 2 heads use the stock valves and are ported by hand. The stage 3 heads use CNC programming so each set is identical and flows exactly as advertised. They also use Manley oversized valves for more air/fuel and exhaust gas movement. The stage 3 heads are definately the way to go in my opinion.

Horsepower numbers vary a ton based on other mods, tune, pulley size etc.. but the heads have been known to add 50 horsepower in some cases.