Yeah, Injen's dyno claims are always questionable and I don't think anyone has ever replicated them independently. People have dyno'd Injens at 0 hp gained on G35's. Granted that's a different motor, but Injen made some crazy claim there too I believe. On a modern car that's not boosted, short ram intakes do very, very little. OEM intakes are plenty efficient and not sucking in hot air. Even if the intake is flowing marginally better, the increase in IAT can result in the ECU pulling timing or other things that decrease power.