Hellion Power Systems' John Urist lays the business end of his company's new Turbonetics 6
Horse Sense: We often use the term "CARB number" when referring to the various aftermarket bolt-on performance parts that we install and evaluate in our tech stories. To end all the confusion, what we're talking about is the California Air Resource Board. The outfit sets the stringent-or ridiculous, in the eyes of most gearheads-guidelines for maintaining air quality in California. The criterion determines the issue of a coveted Executive Order approval number for parts such as blowers, turbos, nitrous kits, and exhaust systems, among other things, that meet its lofty standards.
Calling Hellion Power Systems' S197 Mustang GT turbocharger system "new" could be considered an oxymoron, since it debuted at SEMA more than a year ago-your author even cited it as one of his "Top-10 Mustang Parts" of the show. We've been waiting in the weeds since then for an opportunity to tell you more about it. Hellion's turbo system for '05-'07 4.6 Three-Valve 'Stangs ($5,165) is the brainchild of John Urist, the popular '03 and '06 champion of NMRA Super Street Outlaw. John co-owns the company with Dwayne James, the NMRA Outlaw 10.5 racer.
This system is based primarily on a Turbonetics 62mm turbocharger (7-10 psi of boost), an air-to-air intercooler, an elaborate system of 3-inch stainless steel, and hot-side tubing built by Bassani Xhaust that fits like a glove. The Hellion turbo kit for '07 GTs differs slightly, due to changes made to the routing of the cooling-system plumbing. Other major components include Ford Racing Performance Parts' 39-lb/hr fuel injectors, a Turbonetics Evolution wastegate, a bypass valve, conical air filter, torque clamps, T-bolt clamps, V-band clamps, mounting bolts, and a 4-inch polished inlet tube. A detailed set of instructions is also included, making installation do-it-yourself possible, with or without a twin-post or drive-on hoist to lift the car. Notice that we make no mention of high-volume fuel pumps or pump enhancers. And, unlike several other forced-air systems, there isn't a preset plug-and-play tune for the S197's Spanish Oak processor-and for good reason, which we'll discuss later.
"I wanted to develop a turbo system for new Mustangs that would fit similar to a factory-installed unit and make good, efficient power with the Three-Valve modular engine and stock fuel system," John says. "I also wanted to produce a turbo kit that doesn't compromise the design or function of the S197's factory emissions system. It could potentially be endorsed by CARB as legal for use on registered/emissions-inspected street 'Stangs in all 50 states."
The second part of John's intent is the idea that really intrigues us. Sure, we've seen and evaluated plenty of smog-legal, high performance Mustang parts-power adders included-but street turbo kits are another story, as there are few, if any, CARB-approved systems available for 'Stangs of any vintage.
So when John asked us if we wanted to take part in installing Hellion's long-awaited Mustang GT turbo system and dial it in with DiabloSport tuning software on Charles Lee's brand-new '06 GT, you can imagine how quickly we said yes.
Disconnecting the negative battery cable is always the first order of business. With that task complete, John removes the airbox and inlet, drains the engine's coolant, modifies the upper and lower radiator hoses, and repositions the lower hose and thermostat housing to make room for the turbocharger.
Modifying the radiator hose includes removing a small section and inserting the included piece of splice tubing to replace the removed section. It routes coolant flow away from the front of the engine. All the factory hose clamps are reused during this step.