Originally Posted by Jan Niemi
I have a hard time believing that bolting on a JDM header with everything else on the car stock will net 15-20whp, but if Trey has done it - then that's how it is. Good luck in your search for power.
Jan, not quite what we've said. My car for example made 8whp peak with just the addition of the JDM ITR header and 2.5" cat, with the exisiting AEM CAI and 18 degrees ig. timing. Now of course, compared to stock the following did net a ~25-30whp gain (variable since dynos were done on different days): AEM CAI, JDM ITR 4-1, 2.5" cat, 2.5" exhaust, VAFC, advanced timing. But that's on a crappy stock intake GS-R so that's pretty useless for here. The AEM on the ITR produces far less effect than on the newer GS-Rs.