SP Engineering Nissan R35 GT-R - Import Tuner Magazine

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.

Transmission Woes And Upgrades

"We were starting to make really good power but one problem we just couldn't clear was shifting," says Sumino. "The more power we made, the worse this problem got." The GT-R factory ECU is interfaced with the car's transmission control module (TCM). Upon testing a number of aftermarket stand-alone engine management systems, SPE learned that even if the engine had been tuned to run optimally, because of the integration between the ECU and TCM, the transmission would refuse to up-shift at any more than 700 lb-ft of torque, causing the transmission's internal clutch baskets to lock up and the engine to over-rev. Even the almighty Haltech Platinum Pro, which both SPE and Haltech engineers spent manipulating for ten days on the dyno, ran into problems-the transmission wasn't happy with the constant 4.5-voltage output signal from the MAF sensor being sent to the TCM.

"We knew the shifting problem was related to the car's TCM and possibly something mechanical within the GR6 transmission," says Shen. "So, we decided to upgrade our transmission with a Dodson Motorsports eight-plate clutch kit (OE has only six pucks), PPG first gear, Dodson AWD gear lock, and Exedy clutch packs. The factory clutch baskets were replaced with Dodson billet high tensile steel clutch baskets and pistons to eliminate flexing and distortion of the clutches at higher rpm, and the TCM to automatically trigger limp mode."

The SPE crew worked many late nights and finally found a solution in Cobb's Protune software maps. "We weren't sure if it was going to work but we kept going at it," says Shen. Working closely with Joe Graham from Cobb, he offered revised beta maps to adjust the transmission's clutch torque tables, which SPE received through emails, and tested in a trial-and-error process. "The TCM is very fussy about clutch slip and the various torque signals that go between the ECU and TCM," explains SPE chief mechanic Jason Reinholdt. "Altering the factory clutch torque maps enabled SPE to make sure the communication between the ECU and TCM were in sync, while keeping the clutches locked up at full throttle. If the clutch is slipping, we subtract 10 percent of the torque load to reduce slippage," SPE went through three revised beta pro tuner software versions before they were finally able to find a map that was able to support the engine's power. With all the bugs worked out of the transmission and engine, boost was raised to 29 psi, making 860 whp.

Inspired by the exceptional power gains, Greddy developed the larger Type-29 HG cross-flow intercooler kit to support the turbo kits at full boost. The very first production kit was air freighted to Las Vegas, NV, to SPE's customer Hing Yim, owner of a black '09 GT-R. Yim would accompany the SPE GT-R to the drag strip in Arizona in less than a month.

Race Day

The day started off at 7:30 a.m. with the opening of the Speedworld Dragstrip's gates. Track owner Bernie Longjohn allowed SPE to privately rent the track for the day. The SPE crew, with Yim in the black GT-R, was accompanied by the Greddy crew to finally witness the fruits of their labor. Yim's GT-R sported a slightly milder build compared to the SPE GT-R, while sharing the same Greddy TD06-20G twin turbo kit. The day was a warm 92 degrees, with track temps as high as 120 degrees.

Both GT-Rs began their initial runs without launch control to see what times they could pull. SPE's GT-R managed a 10.77@145 pass with a low boost setting of 18.9 psi, while Yim ran a 10.76@135. In opting not to use the launch control system during the first few runs, the team had a good understanding of the current suspension setup. As the morning progressed, the teams were able to tweak various settings to improve the balance of both cars. After finalizing the calibrations, the SPE GT-R tripped the light in fifth gear with a blistering 9.62 at 149.8 mph, officially owning the title of the world's quickest R35 GT-R. Yim's car followed suit to run a best pass of 9.84 in the quarter mile for the title of second quickest GT-R in the world-an amazing feat, considering both GT-Rs remained in modified street trim, with full interiors and DOT-approved tires.

"It was a long process from our initial build, but it was all worth it in the end, especially when both cars ran 9-second passes all day long under the hot sun," says Shen. "It shows us how impressive the GT-R really is."

Greddy Performance's Kenji Sumino

"When we first installed the Greddy turbo kit, we never thought we would be running 9-second quarter miles. But as we started to work day after day, night after night on this build, it became our goal. Even though the build of both GT-Rs was very frustrating and tiring, it took all of us back to our more youthful days when we wrenched through all hours of the night, and it got us hyped. We were able to learn so much about the car, and setting the new world record was a great experience, but we're not done yet! Greddy is developing a stroker kit and a bigger turbo setup that's currently under wraps. Hing's car will also get similar engine modifications in the future, and we hope to return to the track and improve our times (if we haven't by the time this article comes out!) Hing just texted me recently, 'can't wait to hit 8-seconds' . . . and he was serious."

Up Close And Personal with Alex Shen

From the day you purchased the vehicle to today, did you ever imagine you would one day be holding the world record?
Honestly? No. Records are meant to be broken and that's what makes competition so exciting. Building a high performance vehicle like the GT-R to perform as a reliable street car was our main goal. Breaking records was just icing on the cake.

What was your initial reaction when you heard AMS Performance was the first to break the 9-second barrier in the Nissan GT-R, with a 9.90@146 quarter-mile time?
I thought it was a great accomplishment for them with a car that weighs 3,800 lbs., and before that, I didn't think it was possible. I definitely saw the light at the end of the tunnel.

Were you gunning to beat the AMS record once you heard the news?
Not really. Actually, our customer Hing Yim, who currently owns the second quickest GT-R in the world, wanted to beat their time. We were more concerned with building a reliable 9-second street car. At the race track in Arizona we removed the rear wing, thinking it would improve the vehicle's trap speed, but due to the GT-R's amazing aerodynamics it made little or no difference.

There's been a heavy influx of aftermarket turbo kits for the GT-R lately. What are your thoughts?
A lot of these companies copy the JDM products and brand them as their own kits. Knocking-off a product is much easier than spending long hours and research money to manufacture a product from scratch, but I think it's bullshit. I've seen R35 turbo kits that use parts lying around in a garage, like turbo actuators from WRXs. The fitment is terrible, not to mention they sit right on the GT-R firewall so when the motor torques, the parts are rubbing all over the place. Everyone needs to understand that using quality parts is important, especially on your own $90K investment. A lot of inferior parts are floating around in our industry, and we need to all be aware of the repercussions of using that garbage if we expect our market to survive.

Have the words "world record" finally settled in now that it's been three months since your Arizona run?
It's a great accomplishment to hold such a prestigious title, but like any record, this one will be smashed at any moment. We've made great strides over the past year with the VR38DETT engine, but we won't stop just because we hold a record. We want to keep forging ahead to improve the performance of the GT-R, to make it faster and more powerful.

Future Upgrades:
Greddy 4.3L stroker kit
Cast iron ductile sleeves
Modified oil pump
Greddy hybrid turbo w/modified Garrett turbine wheels (SPE spec)
OS Giken LSD
SPE-spec ported cylinder heads
Ferrea valve train
JUN 262-degree duration intake/exhaust cams
Cosworth head gasket
SPE-spec 98mm forged pistons
Target output: 1,300 hp

From Alex Shen: "I would like to thank Greddy USA for all their hard work and late nights; Bride USA for supplying a pair of Stradia racing seats; Mickey Thompson for delivering tires when we asked them only days before our race; John Shafer and Joe Graham of Cobb Tuning for providing us the latest software updates; Bernie Longjohn of Speed World in Arizona for allowing us to rent out the track on such short notice; and most importantly, my fantastic crew at SP Engineering.

SPE R35 GT-R Mods:

SPE1000 turbo package
SP Engineering fuel system upgrade
COBB Access Port with SP Engineering custom tune
Greddy TD06SH 20G turbos
Greddy Type 29 cross-flow intercooler kit, blow-off valve, piping
Titek titanium race mid-pipe
Titek 90mm titanium race exhaust
9.5:1 compression CP pistons
Carrillo rods
OEM Nissan rod and main bearings
Injector Dynamics 1,000cc/min injectors
HKS EVC
HKS AFK
HKS spark plugs
HKS Hipermax III suspension
HKS DCT transmission cooler
Dodson Motorsport six-speed transmission gear set
Custom SP Engineering transmission map
Swift sway bar set
Project Mu HC+ brake pads
BBS LM street wheels (20x9 front, 20x10.5 rear)
Volk TE37 track wheels (18x10.5 x4)
Mickey Thompson ET drag radials (305/35-18)

YIM's R35 GT-R Mods:

SPE900 turbo package
Greddy TD06SH 20G turbo Kit
Greddy Type 1 dual intercooler
Greddy blow-off valve and intercooler pipe kit
Greddy Version 2 94mm titanium exhaust
Greddy 94mm titanium mid pipe
Injector Dynamics 1,000cc/min injectors
SP Engineering fuel system upgrade
COBB Access Port with SP Engineering custom tune
HKS EVC
HKS AFK
HKS DCT transmission cooler
HKS spark plugs
Dodson Motorsport transmission parts
Exedy clutch packs
Volk Racing G2 wheels (20x9 front, 20x10.5 rear)
Nitto drag radials (275/35-20 front, 305/30-20 rear)
*Record run set on Mickey Thompson ET Drag Radials (305/35-18)

Greddy TD06SH-20G Turbo Upgrade Kit

Turbo Specs:

Compressor wheel: 52.6mm inlet diameter / 68mm outlet diameter
Compressor cover: 80mm inlet diameter / 50mm outlet diameter
Turbine wheel: 58.8mm outlet diameter / 67mm exducer diameter
Turbine housing area: 8 cm2
Max Boost 190kpa (28 psi)

Kit Spec:

TD06SH-20G turbocharger
Greddy Type-R wastegate
Greddy stainless exhaust manifolds
Airinx air filter
Stainless 60mm downpipes
Polished, mandrel bent aluminum piping
Hardware

Optional Intercooler Upgrade:

GT-R R35 Greddy Type-29 HG cross-flow intercooler kit
Core Spec: 700 mm x 302 mm x 115 mm
Polished core and end tanks
Twin 80mm inlet and outlet
Cross-flow type

Optional Upgrade:

GT-R Greddy aluminum piping kit with Type-RZ blow-off valves