Written by Alan Cesar
From the Dec. 2012 issue
Posted in Features
Tuners and race shops alike are flocking to the new Scion FR-S and Subaru BRZ twins. There’s no doubt this chassis is popular. Shops are scrambling to develop show-and-go parts, but it’s early in the game. No one yet knows the driveline’s weak points or the potential fitment issues that’ll crop up once upgrades start coming along. Since Subaru had a strong hand in the design of the underpinnings, there’s plenty of speculation as to what WRX and STI parts may swap.
Begin With What You Know
Phil started the way we’d expect, considering his access to STI parts: He went looking for what would swap over. It wasn’t much. “It’s a unique setup, and it uses few Subaru suspension parts,” he said of the Scion. “The rear lower spring perches are close enough to the STI part to work, but they’re not identical.”
His shop fitted a set of BC coil-overs with custom valving all around, and a pair of camber plates up front. The only other change so far has been to remove the rear anti-roll bar; the car handles better without it.
Matching those suspenders is a temporary set of Hoosier tires; the OEM all-season meat, naturally, just wouldn’t work on a track car. Element Tuning’s FR-S came to the Grassroots Motorsports Ultimate Track Car Challenge wearing a square setup: 285/645R18 tires all around, borrowed from his 2006 STI. Those R80-compound Hoosiers are seated on 18x10-inch Rota DPT wheels.
It won’t stay that way, though: With a goal of 500 horsepower to the wheels, Phil is scoping out sizes used on Corvettes to get an idea of the rubber his FR-S will get. The rears will almost certainly be bigger. “We have room for even more tire back there,” Phil said.
Its current wheel-and-tire package actually fits under the car’s original fenders with just a bit of pulling. Those carbon-fiber flares on the rear wheels are ornamental for now. Phil set the ride height he wanted, then covered the wheel gap with flares made for an R33 Skyline. The inner fender will eventually get cut up when he fits really big rubber.
Even if some monster meats and big wings can’t keep the rear tires planted, there’s a trick up Element Tuning’s sleeve: Their Hydra EMS is capable of handling traction control duties, too.
Those big brakes up front? They’re also from the 2006 STI, plumbed using the Scion’s rubber brake hoses. All you need for this swap are the calipers, brackets and rotors. The rotors have to be from a 2004 STI, though, due to the 5x100mm wheel bolt pattern. The only trick to the job is to swap the left- and right-side calipers: They mount behind the axle on the STI, but in front on the FR-S.
While performance pads are readily available for the STI’s Brembos, they don’t yet exist for the FR-S sliding single-piston rear calipers. Phil ordered a set of OEM Scion brake pads and sent them to the crew at Carbotech, who removed the original wear material and replaced it with their own XP12 compound.
Where’s the Power Now?
A simple turndown after the catalytic converters replaced the stock exhaust system; horsepower is essentially unchanged. The rest of the powertrain is as delivered. Engine tuning and development is a big target for this car.
Element Tuning knows boxer engines well, but this car’s fuel delivery system is in another dimension. The flat four-cylinder engine has both port and direct injection. That fuel delivery system is one of Toyota’s major contributions to the project: Direct-injected boxer engines didn’t exist before the FRZ. (Or is it BR-S? We’re still not decided.)
The shop’s preferred Hydra engine management is capable of driving a direct injection system. Initial tuning is tricky, though; timing has to be much more precise in direct injection than with traditional port injection. “We used a high-resolution PC oscilloscope that can take up to 32 million samples per trace, making it possible to capture complex automotive waveforms, including CAN Bus and FlexRay signals,” Phil said.
Its horsepower output is still stock, which is a far cry from the goal of 500. Element Tuning is going to build up to that incrementally in an effort to suit multiple levels of tuners. “Let’s face it, there’s a lot of guys who won’t do much more than tuning—who won’t turbo it,” Phil said. “We’ll do the E85 tuning and hopefully get 35 horsepower out of it. This car would do really well to gain 30 horsepower.”
E85 has a higher octane rating than pump gas, and is both cheaper and more readily available than race fuel. Finding it across the country can make road trips a bit of a hassle, but that’s a solvable problem. Their ECU has support for the General Motors flex fuel sensor, which monitors the amount of ethanol you put in the tank. This way, you can still use pump gas when E85 is hard to find.
Then boost is on the way. Element Tuning hopes to offer a better motorsports-developed and unique turbocharger kit solution. “We want to get in on the ground floor with the engine building, the engine management system, the turbo kits,” Phil explained. “That’s why we’re pushing to get the R&D done. Bigger manufacturers are probably a little hesitant [to develop turbo kits] because it’s not a factory turbo car.”
To make up for some of that off-the-lot power deficit, Element Tuning removed the back seats and everything in the trunk. The car still has air conditioning and, forward of the B-pillars, looks entirely stock inside. We saw Phil with his windows rolled up at the UTCC grid, enjoying the cool comfort inside while others sweated profusely.
The front seats, despite weighing about 40 pounds apiece, stayed in, too—at least for now. “These seats are fabulous. They really keep your body in place,” he said.
Phil almost brought the car wearing major aerodynamic changes. In the shop, ready to bolt up a rear diffuser, he changed his mind. His Scion will eventually become an unlimited Time Attack car with a lot of aero work, but not until it has power to counteract the drag. “I was afraid it would just slow the car down too much. I needed a baseline,” Phil said.
When that time comes, Scion and Subaru will have done a lot of the work for him already. “The bottom of this car is really flat. It’s all paneled up and everything. They do a good job,” he explained. “There’s not a whole lot we have to do underneath, other than a nice front splitter. A diffuser on the back will be just to clean up the air. The bumper and the original exhaust system create a lot of drag.”
Phil was surprised when he started mocking up some pieces, though. “When you look at the car and you buy it, it doesn’t look like a wide car. But this thing is frickin’ wide,” he exclaimed, gesturing with his hands. “I have that fulcrum aero wing on my STI that’s 72 inches, and it doesn’t stick out past the fenders [on the FR-S]. It basically flushes up with the edge of the body.”
Just the Beginning
This car stands as an example of how excellent the FR-S is in stock form, even though it’s underpowered. Soon enough, it’ll have all the goods Element Tuning can strap to it and be as bonkers as you’d expect. We hope to see a transformed version at next year’s Ultimate Track Car Challenge.
Does this mean the shop’s mad-as-a-hatter STI is getting shelved or sold? Fat chance. “At this point, we don’t know if this will be faster than our STI, so we’re not planning on replacing it,” Phil said. We’re eager to see the result.
Phil Grabow would like to thank Hydra EMS America for developing the computer with Element Tuning, and BC Racing for building custom suspensions to their specifications.
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4 days ago in News
The drawing closes on November 6.