You know Signal Auto for its ostentatiousness, for its signature-orange paint schemes, for being the company responsible for turning out cars like its legendary pair of chop-top JDM Civic drag cars—one of which was powered by a front-wheel-drive NSX platform—or its equally infamous 180SX duo that did their part in helping establish drifting in the U.S. But there's more to the Osaka, Japan-based tuning firm and parts manufacturer, and their story transcends any requisite color codes or purpose-built race cars.
Officially founded in 1978 by Kosuke "MAD" Kida, today, Signal Auto does it all. The JDM powerhouse's list of services on its website tells you that its auto body side is equipped for jobs as small as repairing a single scratch or dent, but limiting Signal Auto to something as menial as all of that would be foolish. Deep in its suburban headquarters, the Signal Auto team thrives on unparalleled undertakings—like Civics with their roofs lopped off, shortened, and then grafted back into place. Big-power engine builds that aren't limited to any particular make, body work, tuning, and fabrication all make up the list of what the Japanese tuning company is capable of and complement its manufacturing side that produces high-end aero pieces, exhaust components, and engine bits. Over the years the JDM firm has expanded and then scaled back, opening up a North American facility in Torrance, CA, in 2000, which has since been shut down, as well as another location in Thailand.
Not every Signal Auto buildup is as glorified as those that have made their way onto American soil, though. In between every iconic Signal Auto project are two more that are every bit as attainable as the others are majestic. Like the company's most recent JDM creations—its STi-swapped GC8 Subaru WRX and moderately modified R34 Nissan Skyline—either of which are orders of magnitude more realistic than what the company's been known for in the past but, in their own way, every bit as special.
You can't just go out and buy your own GC8 WRX—the upgraded Impreza based upon Subaru's World Rally Cross cars wasn't available to American buyers until '02—but if you could, you'd want it to be like Signal Auto client Yasuhiro Kimura's. The Osaka tuning company started with the JDM WRX's original boxer engine but soon pulled the short-block out from underneath it, replacing it with the later-model GDB STi's stronger, more powerful version. It's an obvious swap that's done for obvious reasons: the cylinders, pistons, connecting rods, and crank are all able to handle more abuse.
Which is a good thing since the pressure was promptly cranked up, although, interestingly enough, the original turbo was retained. Here, the factory turbine bolts up to a Maxim Works exhaust manifold that's fed from the other end through a Blitz intercooler and a host of piping from Signal Auto and Zero Sports. Signal Auto dialed in the EJ20's air/fuel mixture using an A'PEXi Power FC along with Power Enterprise injectors and a SARD fuel pressure regulator. The results are every bit as tame and streetable as you think, which is, after all, what Kimura was after.
Like most of Signal Auto's demo cars, Kimura's GC8 exacts balance. The moderate power level complements the pointedly modified chassis that's been outfitted with Zeal shocks, Hyperco springs, and just about every bar, brace, and bracket that Cusco says any Impreza ought to have. It's the same sort of balance that's inherent with Subaru's boxer-engine layout. Unlike conventional inline or V-style engines that distribute their weight unevenly across the chassis, boxer engines are nearly symmetrical. Rip the car in half from front to rear and the two halves of the engine, transmission and driveline are identical to one another. Do the same to any inline or V-style engine and you'll end up with an exhaust manifold on one side, maybe three-quarters of a crank on the other, or an entire transaxle on one end. Such boxer symmetry leads to reduced body roll, less torque steer and reduced engine vibrations, or, in other words, the perfectly balanced WRX that you've always imagined.
1998 Subaru Impreza
Engine GDB WRX STi engine block; Tomei headgasket and timing belt; ARC oil pan; Blitz SUS Power air filter; Zero Sports intake pipe; Trust Spec-R intercooler, oil cap and spark plugs; Signal Auto custom intercooler piping, titanium exhaust, radiator and radiator cooling plate; SARD blow-off valve, front pipe, fuel collector tank, fuel pressure regulator and radiator overflow tank; Maxim Works exhaust manifold; R34 Nissan Skyline fuel pump; Power Enterprise 550cc/min. fuel injectors; HKS oil cooler; Cusco oil catch tank; A'PEXi Power FC; Samco Sports cooling and induction hoses; WRX STi radiator cap
Drivetrain GC8 transmission; Exedy Hyper carbon twin-disc clutch; Cusco 1-way differential (front); Cusco 1.5-way differential (rear)
Footwork & Chassis Zeal Super Function shocks; Hyperco springs; Cusco front and rear upper shock mounts, front and rear stabilizer bars, front and rear strut tower braces, front and rear lower arm bars, center floor brace, rear floor brace and trunk brace; Okuyama 13-point aluminum roll cage
Brakes Endless six-piston front calipers, front rotors and pads; Dixcel rear rotors
Wheels & Tires 17x8" +45 Yokohama Advan RS wheels; 225/45R17 Yokohama Advan Neova AD08 tires
Exterior Signal Auto canards, custom front and rear diffusers; Garage Kagotani carbon-fiber hood; Sard GT Fuji rear spoiler; Ganador carbon-fiber mirrors
Interior Bride Zeta III seats; WRX STi shift knob and 280km scale gauge; Sard gauges; Defi Racer boost gauge, Billion VFC Pro fan controller; TRUST Profec B boost controller