Greddy T518Z Tuner Turbo Kit For Scion FR-S/Subaru BRZ - Import Tuner Magazine

Over past year, the Scion FR-S has received more hype than any sport compact car on the market, and with good reason. From its unmistakable styling cues to its sleek exterior design, the FR-S with its lightweight 2,758 pounds (manual) and 2,806 pounds (automatic) curb weight offers a well-balanced chassis that handles well both on and off the track. The FR-S, with its rear-wheel-drive configuration, had been a longtime coming since Toyota decided to reintroduce a RWD sport compact vehicle to the U.S. market--something that has not been done since the sale of the third-generation MR2. Coupled with a factory-equipped Torsen-type LSD, traction control, short-shifter-equipped RA62 six-speed, and an A960E six-speed automatic transmission with paddle shifters that's both responsive and quick and you've got none other than a car that drips in DNA motorsports heritage.

By far the biggest controversy of this car has been the 4U-GSE engines. The flat-four boxer engine was a joint collaboration with Toyota and Subaru. The low-mounted, naturally aspirated, 200hp, rev-happy boxer engine enables the FR-S to achieve excellent weight distribution and the lowest COG ever for a production vehicle. The FR-S's 2.0L naturally aspirated four-cylinder engine combines Subaru's newest horizontally opposed engine and Toyota's cutting-edge D-4S injection system, which incorporates both direct injection and conventional port injection for each cylinder. D-4S technology donated from Toyota to Subaru boxer engines uses eight injectors, four injectors fire separately for direct injection and the remaining are for port injection. The D-4S system, partnered with a high 12.5:1 compression ratio, results in delivering a factory-rated 200 hp and 151 lb-ft of torque.

Inspired by a collaboration of rear-drive Toyota models that date back as early as the '60s, which include the Sports 800, 2000GT, and the AE86 Hachiroku, Toyota engineers took a page out of the popular AE86, a vehicle that the FR-S sports car carries many similar features. Both cars are recognizably lightweight, agile, and popular among drifters and tuners alike. Unfortunately, neither model is fast or luxurious, which is as expected with any mid-priced sports car.

Sooner or later it was bound to happen. Within days of introducing the FR-S, the horsepower hungry tuner crowds quickly gathered in unison and began chanting the familiar tune: "We want more power!" Toyota engineers turned the deaf ear, proclaiming there wasn't room for an additional power adder, such as a turbo underhood, but aftermarket tuners like Greddy Performance Products clearly saw that simply wasn't true.

Since the debut of the FR-S, no other performance company has invested as much time and effort as Greddy. Greddy's dedication to the newest sport compact car has become a long-term commitment, thanks to their long-standing relationship with Scion that's dated back to 2004. A lasting relationship that birthed their presence in Formula D with the full support of Ken Gushi and his 600hp Scion FR-S drift car, marketing the enormously popular Rocket Bunny widebody kit in the United States, and most recently, the mass production of their highly anticipated bolt-on turbo kit. We first caught glimpse of the turbo kit at the Tokyo Auto Salon as Greddy's parent company, Trust, teased us with their prototype.

It was as early as July of 2012, when we first received news that Greddy was engineering an aftermarket bolt-on kit. A quick call to Mike Chung, planning manager of Greddy USA, confirmed the news that the FR-S kit was in the closing stages of completion. We were invited to their Irvine, CA, headquarters to document the installation as well as witness a dyno tune of the vehicle, which happened to be Ken Gushi's personal daily driver. "The Greddy Tuner Turbo kit highlights the lightweight, fun, and easy-to-drive characteristics of the FR-S with minimal sacrifice in fuel economy. We designed an aftermarket kit to safely and reliably complement the boxer engine for use with the stock injectors and OEM fuel pump. In order to keep manufacturing costs down, we are leaving the fuel enrichment option up to the individual tuner. Depending on how extreme they want to go, the tuner has more options for aftermarket ECU/fuel tuning as their horsepower demands increase," Chung says.

Greddy T518Z Tuner Turbo Kit:

• Greddy T518Z - 10cm2 Turbocharger with Actuator (Greddy original compact 18G turbo)
• Trust, 4-1 stainless steel header-type exhaust manifold with dual flex pipes
• Stainless steel downpipe (60mm diameter) with 40mm wastegate outlet
• Airinx AY-SB (70mm) air intake
• Lightweight Greddy tube and fin front-mounted intercooler (compatible with Greddy Circuit-Spec Oil Cooler Kit)
• Aluminum charge pipes (50 to 70mm diameter) and reinforced silicone hoses couplers
• Aluminum heat shield, mounting brackets; gaskets; mounting hardware and rubber lines.

Sold as an intercooled, racing turbo system, the Greddy FR-S Tuner kit has been tested (with aftermarket ECU tuning) to deliver an additional 100 hp at a Greddy preset boost level at a conservative 7 psi of boost due to the engine's high compression ratio. Delivering the newfound 248 hp and 197 lb-ft of torque output is based off of the Mitsubishi Heavy Industries (MHI) TD05H-18G manufactured as a Greddy T518Z turbocharger. The TD05H-18G has been a longtime favorite among performance enthusiasts as the 2.0L boxer's cramped engine layout benefits from the turbo's compact design. The 10cm² exhaust housing's larger scroll area helps to maintain minimal lag throughout the engine powerband, something you'll appreciate once the turbo quickly spools to a set 7 psi of boost and pins you to the back of your seat. The Greddy T518Z features a compressor wheel that measures in with a 50.5mm inducer and 68mm exducer (55.1 trim piece). The turbine's 76.87 trim comes from a 49.1mm inducer, and the 56.0mm exducer is capable up to 421 hp.

Among many of the quality components sold with the Greddy kit is a Type 40E front-mounted intercooler that sits tucked away behind the front grille. The Type 40E intercooler is the newest design to come out of Trust Japan. Measuring in at 400x287x68mm, the intercooler might look small in stature, but don't let the looks fool you. The 40E core offers a new shape of inner fin design for improved cooling efficiency and less resistance, which allows their engineers to design an intercooler that's compact, yet allows for ample room between the radiator core and bumper structure for a "straight shot" charge pipe design to minimize boost lag. The intercooler shown is a prototype unit. The final production kit will be using cast end tanks.

Greddy specifically designed the Greddy Tuner Turbo kit to fill in power where they thought the former naturally aspirated car could use some horsepower and torque improvement. In conjunction with a top-mounted Greddy T518Z - 10cm2 turbocharger (18G turbo) and a handmade 4-1 equal-length header, the kit offers a healthy improvement in midrange performance from 3,000 to 4,500 rpm.

Ken Gushi's FR-S Driving Impressions:

"I often get asked on my initial thoughts of the lack of horsepower in the FR-S. To be honest my daily driven FR-S performs great. It doesn't feel like it lacks in the horsepower department that so many of the tuner crowds have addressed. Overall, the car prior to the Greddy turbo kit felt very well balanced when driven on the streets and highways. Modern cars have a tendency to handle like a larger-sized domestic or minivan but the FR-S still maintains that 'raw feel' every time you flick the steering wheel or take on a tight turn while mashing on the accelerator without having to worry about losing control. Toyota/Scion wanted to develop a fun-to-drive, sporty hatchback--and thankfully, in that regard, the FR-S delivers.

"The car was bone stock for roughly one week before we decided to install a Greddy Momentum intake and Evo3 exhaust, which helped increase gains of 14 whp, so in that essence the car felt good from the get-go. Upon installing the Greddy Tuner turbo kit, it delivered a night-and-day difference in how the car performed. Not only did it raise the engine output by 100 whp, but was accomplished without any modifications to the OEM injectors or fuel pump".

"In its naturally aspirated form, the FR-S has been known to develop a power loss from 3,000 to 4,500 rpm. The turbo kit (with ECU tune) not only addressed this issue but also enabled the vehicle to increase power throughout the midrange all the way to redline with minimal turbo lag. Simply put, the T518Z turbine works perfectly with the 2.0L engine and doesn't have you saying 'lag, lag, lag . . . boost!'-a typical scenario with turbo setups using larger-sized turbos. The near-instant torque and boost response almost makes the car feel as if it was meant to be turbocharged from the factory. With an extra boost in power, the car still maintains good balance, although I recommend an aftermarket clutch to handle the newfound horsepower. It doesn't take a genius to recognize that the turbo kit delivers more power and torque all the way to redline than the previous NA setup, making for a very satisfying driving experience."

Test Car Specs:
Ken Gushi's '13 Scion FR-S (Six-speed)

• Greddy 70mm Evo3 cat-back exhaust system (10117302) 70mm to dual 70mm (MSRP: $860)
• Greddy Circuit Spec 13R Oil Cooler Kit (MSRP $1195)
• OEM fuel pump and injectors
• Greddy Performance Tuned: EcuTek ROM tune
• Boost: 0.5kg/cm² (7 psi)

Dyno Test

Dyno 1
Stock baseline (green)
Stock: 154.8 hp/128.6 lb-ft of torque

Dyno 2
Greddy Momentum Intake and Evo3 exhaust system (blue)
168.4 hp/137.4 lb-ft of torque

Dyno 3
T518Z Tuner Turbo Kit; Evo3 exhaust; EcuTek ROM tune (red)
248.3 hp/197.2 lb-ft of torque

Dyno testing the new turbo kit showed a gain of 94 whp and 69 lb-ft of torque over our initial stock baseline number. More importantly, we noticed a significant gain at 3,500 rpm of 55 whp and 100 lb-ft of torque. The impressive numbers continued throughout the entire powerband with a pickup of 55 whp and 48 lb-ft of torque at 5,000 rpm.

To see more new and exciting products for the FR-S/BRZ from GReddy, click here.