quote:What type of "cam" characteristics, I meant to write.
Will,
I didn't mean to suggest IR would necessitate a cam change. It's more a matter of optimization.
Like in all other engine combos, cam selection is driven by the other components in your build and the performance characteristics you desire.
But generally, IR can mellow out the low/mid rpm behavior of peaky cams. In other words, you can get away with running tighter lobe separation angles on the street (more overlap) and not suffer the reduction in idle quality and low/mid rpm performance to the extent that occurs in common plenum intake manifolds with the same cam. This tends increase max torque, moves the torque curve toward lower rpm, but can also narrow the powerband a bit. -All depends upon what you're after.
Kelly