While most of us can only dream of owning the quickest car in the world, some will do whatever it takes to possess such speed and power. Since 1996, SP Engineering (SPE) owner Alex Shen has dreamt the impossible dream. In 1995 SPE made 500 whp on a 2JZ engine (the first shop to do so); In 1998, an 812whp 2JZ using strictly bolt-on parts. And in 2003, they earned bragging rights with Ken Henderson's 1,126whp daily-driven Supra (Top 5 Supras, Oct '10 2NR). On April 11, 2010, Shen joined an elite group of 9-second GT-R owners, shattering a world record held by AMS Performance, with a time of 9.62 seconds at 149 mph (AMS's previous 9.894@145.96 record was set two weeks prior). A pipe dream had become a reality for Shen thanks to his determination and his dedicated staff of mechanics.
If the car looks familiar, that's because it appeared on the cover of our October '09 issue. After our cover shoot, the R35 was disassembled, and SPE committed months on R&D to enhance every part of the vehicle, from replacing the engine's internals to upgrading the factory turbo system. It had been over a year since we last saw the GT-R, and it was now delivering an impressive output of 848 whp and 866 lb-ft of torque at 28.6 psi of boost, brought about by twin Greddy TD06SH-20G turbos and a Type-29 cross-flow intercooler.
"The goal was simple," says Shen. "Pick and choose parts available off the shelf and build a reliable car while retaining amenities like air conditioning and audio." SPE joined forces with Greddy in August of '09 and began testing numerous products, including a prototype Greddy turbo upgrade kit. At the time, both teams were well aware that the tuning software and engine management systems on the market were still in the early stages of development, but decided to take a leap of faith. "We teamed up with SPE knowing they are one of the top tuner shops in the U.S., with extensive knowledge of the R35," says Greddy USA president and general manager Kenji Sumino. "Alex's GT-R served as the perfect vehicle to test our newly developed parts.
Disaster Strikes
Nissan engineers knew exactly what they were building when they developed the VR38DETT twin-turbocharged 3.8-liter V-6-a race-bred engine detuned for street driving. While dyno testing the car one night, tragedy struck the GT-R, causing massive engine failure. SPE senior mechanic Hirofumi Kondo disassembled the engine to find the number four and six cylinder piston ring lands were cracked. Rather than replace the stock parts, SPE upgraded to a set of forged CP pistons and Carrillo rods, along with bumping injector size from 850cc/min to 1,000cc/min. A Greddy TD06SH-20G turbo upgrade kit and custom dual-feed fuel pump system were the final key ingredients installed before deciding an aftermarket engine management system was integral in order to make additional power.
"Initially we had our stock-replacement Greddy Type-6 Intercooler kit on the car," says Sumino. "SPE first attempted to tune with a couple different engine management systems and was able to produce 650 whp at 20.3 psi of boost. We wanted to increase boost pressure to see the full potential of the turbo kit, but the car was not operating at 100 percent, and had drivability issues."
During the next few months, the build progressed at a rapid pace with many late nights of tuning, but the SPE and Greddy crews continued to scratch their heads and pray for new map updates. Using their Platinum Pro engine management system, Haltech engineers joined in on the festivities to decipher the GTR's ECU, and found success-the Haltech system enabled the engine to produce 778 whp at 23.2 psi of boost. And then the transmission refused to shift.