It picked up 15 hp over the Wilson ported M1 intake. I can't compare it to an as cast Indy intake since I don't have one available but maybe 20 or 25 hp improvement over the Indy unit. The intakes that Indy sell are pretty rough when they come out of the box. The port size is irregular and the plenum is a bit of a mess. If Indy would spend 15 minutes running a CNC around the ports their stuff would be a lot nicer and would work better.