Yes, that's a good question, with an ecu like tec iii OR HALTECH, hicas must be disabled, as those ecus are fully programable for any vehicle and probably do not have options for vehicles with 4 wheel steering specifically Nissan HICAS. My intentions are to have the fastest track car i can get without loosing streetability. Probably going to re-build the internals at some point with an objective of 20Psi boost running open wastegate. Probably go all out on the internals including High RPM valvetrain and 450 lift cams, from ISKY.