The Z tends to do worse under higher power applications on the track is what I've personally noticed. Once you start seeking the higher hp #'s it can hamper you on the more technical areas on the track. This is directly related to the engine and how the car puts the power down. Newer cars with newer technologies are becoming better at laying down torque on technical tracks. The RB does well obviously through the GT-R's 4WD, but also due to powerband torque curve. The higher the HP's against each other the more this became apparent. Stock HP levels the difference is negligible.
1992 Nissan Skyline GT-R Gunmetal Gray - Long Live the Z and Godzirra! - "Love cars. Love people. Love life." - Mr. K.