I would go GSR, instead of ITR or CTR, personally.. get the B18C. That motor is a great motor, and that's the motor you see the best gains out of. plus the itr is friggin' expensive
B16B (CTR):
1595cc (DOHC VTEC)
Horsepower: 185hp@8200rpm
Torque: 118lbs-ft@7500rpm
Compression: 10.8:1
Bore: 81mm
Stroke: 77.4mm
OBD: 2
Redline: 9000rpm
B18C (ITR):
1797cc (DOHC VTEC)
Horsepower: 210hp@8100rpm
Torque: 134lbs-ft@7500rpm
Compression: 11.0:1
Bore: 81mm
Stroke: 87.2mm
OBD: 2
Redline: 8900rpm
B18C (GSR):
1797cc (DOHC VTEC)
Horsepower: 178hp@7600rpm
Torque: 129lbs-ft@6200rpm
Compression: 10.6:1
Bore: 81mm
Stroke: 87.2mm
OBD: 2
Redline: 8200rpm