Here's a question that was asked on an older thread: You may feel like you're getting improved power with the change of an I/C, but the real question should be, why? Here's what I found last w/e when I finally installed a GPIC to my car: (AFR datalogging) Stock I/C: GPIC: While of course every car is different, I saw an avg. increase of 0.7 in my AFR, so of course the car felt slightly stronger, and while 0.7 isn't a lot on a stock tune, because of the factory tuning rich, I would recomend that if your car has been tuned with one I/C, you may want to check with your tuner to see if that much of a difference "may" matter. I for one absolutely made some changes to compensate for this. (oh, and there were some minor changes in timing because of this also, but the ECU would handle that compensation easily, tuned or not, unless of course you wanted to make those changes too) Again, just food for thought and info to be tossed out there.
Colder air charge, say from a better intercooler, will have a denser air charge and therefore more air molecules. If there is little compensation in the tune by the intake air temp sensor, you will result with a leaner air fuel ratio. Another side effect of more air molecules in the combustion chamber is more HP. Honestly that is a pretty good AFR.
It's even better to have the GP IC and meth. :ihih: Cool makes a car run good and if you get tuned for it you can take advantage of the octane boost from the meth. Its even better with race fuel and meth. The only drawback is needing tires more often.:lol: