No, we are not talking about backwoods moonshine. The homebrew in this case is a potent concoction that's designed to really get your pulse racing, bring on a sweat, and get ya' begging for mercy. This is a Subaru RS that out-WRXs the WRX with a 400-plus horsepower motor and a ton of attitude.
Zaidoun Al Hilali is not a patient man. When Subaru announced in 1999 that the rally-derived WRX would be available "soon" in the USA, Zaidoun got tired of waiting and decided to build his own version of the WRX based on the Impreza RS. In 2000, Zaidoun found his car and started turning it into his very own STI WRX V8 killer. This is how he did it.
"I decided it would be smart to build a bulletproof engine because I knew that the stock RS motor would not be able to withstand the kind of boost pressures I wanted to run, so I contacted Trey Cobb at Cobb Tuning," he says. "At the time they were one of very few companies that offered upgrades for Subaru. I explained what I wanted to do and Trey got to work."
Cobb started out with a set of JE custom forged low-compression pistons, Total Seal rings and forged Pauter rods. These were installed on a knife-edged and balanced crankshaft and installed in a blueprinted and O-ringed block. Cobb then ported and polished the heads and installed a set of Manley valve springs and retainers. A set of Web camshafts were ground to Cobb's specifications and the intake manifold was Extrude Honed for maximum flow.
Once the engine was built up sufficiently, Zaidoun turned his attention to the turbo setup. "My options were fairly limited at the time, so I installed the turbo system from a Subaru Legacy. The turbo was a tiny IHI unit that made good bottom-end power but couldn't make any high-end numbers. We used a Spearco intercooler and a Legacy exhaust manifold, water pump and crossmember."
Looking for more horsepower, Zaidoun installed a custom up-pipe and a T3/04E turbo that was a major step in the right direction toward V8-killing horsepower. With the help of custom tuning via a Haltech E6K engine management system, the blue Sube was now hauling ass, but Zaidoun still felt the need for even more speed.
CTC Motorsports came to the rescue with one of its custom turbo units. They also fabricated a custom up-pipe and installed an HKS exhaust manifold and FMIC with custom made piping. A Tial 35mm wastegate controls the boost, while a computer-controlled water spray system cools the intercooler, just like on WRC championship WRXs. CTC also managed to squeeze in the oversized 3-in. downpipe.
The Haltech management unit controls eight injectors, four GReddy 550cc units and four 280cc. A Supra fuel pump keeps the injectors supplied and an XS fuel pressure regulator maintains pressure in the custom fuel rail. A custom built cold-air intake was also installed, and the exhaust is a 3-in. Blitz NUR-spec system. On the electronic side of things, Zaidoun installed a J&S timing computer, A'PEXi AVC-R boost controller and GReddy turbo timer. Just to be on the safe side, an NX Nitrous Express wet system was also installed! I guess some people just don't know when to say enough is enough.