Originally Posted by norcal4banger
But as far as the CAI, it wont do anything? Just louder?
As far as hp and tq gains, maybe 1-3whp above 3k rpm and at 50%+ throttle. If you want as much performance from your 2.7L as you can extract, get CAI by all means. I don't think its worth it IMHO. $300 for 1-3whp is crazy expensive and finding used CAI for the 2.7L is almost impossible.
Don't expect more low end grunt from CAI and header. All these modifications do is they allow more AIR in to the engine and more AIR from the engine. The stock intake and exhaust manifold work awesome below 3.5k rpm and below 50-60% throttle. Toyota designed the intake and header restrictive to some degree so they could keep the engine as quiet as possible without sacrificing much performance, especially below 3.5k rpm and below 50-60% throttle (closed loop) which is where most people are when they drive these work trucks. The stock intake and exhaust manifold becomes restrictive above 3.5k rpm and above 50-60% throttle, choking the engine and not allowing the maximum hp and tq output. By adding CAI and header the engine can breathe and exhale better above 3.5k rpm and above 50-60% throttle, the smart ECU squirts more fuel to compensate for the added air and the engine makes little bit more power. These gains come with the truck becoming louder especially when its above 3.5K rpm at 50-60%+ throttle.