Upping The Ante

With driveability, the interior and exterior addressed, Insumran seeked to increase engine performance beyond the 276 factory horsepower. Known to be able to handle up to 800 wheel horsepower on a stock block, the target horsepower level for Insumran’s street-only RB26 was in the easily attainable 500-to-600 horsepower range. He explains, “While heavily modified GT-Rs have proven capable of well over 1,300 horsepower, I wanted fast response not peak power. I like powering out of the turns on the road course without lag, so I chose the engine performance upgrades with that in mind.” The bottom end remains untouched while a TOMEI POWERED MLS head gasket replaces the factory composite gasket. The upgrade gasket and ARP head studs provide a superior cylinder seal while A’PEXi 270-degree camshafts lift the valves higher and keep the valves open longer to help the engine breathe easier.

With some basic engine upgrades in place, Insumran choose a turbocharger solution to deliver exceptional response and additonal power. After doing some research, his choice was the twin TD06 turbo system from GReddy. Now, a pair of GReddy top-mount stainless-steel manifolds feed twin GReddy TD06-17C turbochargers. These medium-frame turbos deliver quick spool-up and response while raising the peak horsepower ceiling. HKS intercooler piping links the turbochargers to the ARC three-row intercooler. With additional airflow on call from the larger turbos, larger fuel injectors and a tuning solution was in order. Daisuke Kobayashi of Garage Saurus performed a ROM-tune to orchestrate the six-pack of NISMO 550 cc/min injectors. On 93-octane pump gas, the GT-R put down 535 horsepower and 393 lb-ft torque to the rollers of a Dynojet AWD dynamometer at a very conservative, peak-boost level of just 15 psi.

Driveline Drama

Nearly doubling the factory horsepower output proved too much for the notoriously-weak R32 gearbox, as Insumran’s transmission failed soon after reaching the new horsepower level. To eliminate this problem in the future, Insumran installed an OS Giken 5-speed Cross-Mission gear set. Continuing down the line, the rear differential was fortified for improved power distribution with a NISMO 1.5-way limited-slip differential.

No matter how much power is made, every car depends on just four contact patches to get it done. A set of JIC Magic FLT-A2 coilovers set ride height while keeping the wheels and tires in contact with the pavement. BBS LM wheels wrapped with Kumho Ecsta MX tires produce the contact patch. While not the stickiest offerings on the market, the tires provide a great balance of performance and tread life.

Done Deal

After owning the R32 for a decade, Nat has decided that this project has reached its build objective, “I’ve reached the ending point for what I set out to achieve with the R32. I’m happy with the results, and unless I break something else, my vision for this car has been fulfilled. With ten years of knowledge and experience under my belt, I now plan to direct my efforts into my new project car, another fully-legalized Skyline GT-R. My new project is an R33 GT-R V-Spec, Le Mans edition, the only Le Mans edition that was legalized before MotoRex got shut down.” As an enthusiast that understands the value of driving your dream car on the street, we look forward to the R33 GT-R build and hope to see it in a future issue of DSPORT.