Originally Posted by
jrgoswick
I thought the only difference between an ITR and a GSR WERE the cams, compression ratio's, tune in the ECU, and gears in the trans. Was I misinformed?
The ITR was the stop light warrior, the GSR was the highway monster. Gears in the ITR trans are closer than the GSR, which is why the ITR is a little higher strung(my understanding).
The ITR uses a B16A head, but it's ported from the factory.
Compression in the GSR (B18C1) is 10:1, the ITR's C/R is 10.6:1.
The cams in the ITR had a little bigger duration, so VTEC was moved to 6000rpm, where as it's at 4400 in the GSR because of the slightly different cams and dual stage intake manifold.
Redline for the GSR is 8000rpm, ITR had a slightly bigger redline, because of the powerband from the cams and intake.
The trans in the ITR is also a B16 trans, but with a factory helictical LSD unit.
In all, The B18C1 and B18C5 are the same motor, but with a better flowing head, slightly bumped compression and shorter geared trans.