The stealths chamber and ports are direct copy of the RPM heads, just a little more rude and no hand blending in the bowls etc. And the fact that rpm's hgave angled plug, but the mopar performance head is the same except for the straight plugs. Everything bolts on just like in the Stealths, the only major difference being the quality and the looks. I really can't see how the Edelbrock script in the end of the headf makes it a race head, while the Stealth is not? But I guess it's not the only thing in the world I don't understand.