The intake goes into this fender-fed cold air box. You can see a large HKS Powerflow filter in there. It looks like the car used an HKS VPC and got rid of the mass airflow meter, with one large intake instead of the two smaller stock ones with individual MAF’s.
The accessory drive has provisions for an alternator, water pump, and power steering pump and that’s it. The water pump drive ratio was reduced to prevent pump cavitation at higher RPM. The power steering pump is modified for more output. You can see that the lower radiator hose which had a tendency to collapse on production cars has been replaced with hard pipe. What is interesting is you can see a witness mark where the REINIK emblem went. Did HKS peel it off? The engine coil valley cover is removed. This was a normal thing to keep the coils cooler.
I am loving this nice and simple stainless steel under-car dual exhaust. You can see air jacks peeking out under there. Also under the car, there are large coolers for the differential, transfer case, and transmission with pumps to circulate the gear oil to and from the coolers.
Most Group A GT-Rs had 355mm rotor 4 piston Alcon brakes but since the cars were heavy at 2850 lbs, they were plagued by brake fade issues, the HKS cars were retrofitted with AP six-piston calipers and 376×36 rotors. The standard suspension used on the Group A cars was KYB race damper but HKS replaced these with their own HyperDampers. All the suspension links are changed out for ones that are adjustable with bearings instead of bushings.