There are two sides to a turbocharger-the exhaust side (left) and the compressor side (right). An exhaust wheel is spun, which in turn spins the impeller, and the air is compressed and discharged to the engine.
As one can imagine, the turbo head unit runs much hotter due to the 1,200- to 1,600-degree exhaust gases spinning it. The excessive heat affects the inlet air temperature, and almost always an intercooler of some kind is used to cool off the discharge temps. Like the Paxton system, the Hellion mounts the air-to-air inter-cooler right behind the lower front valance. Its location is a high-pressure area that gets a generous amount of air passing over the fins of the intercooler.
The Hellion kit installation took several nights in the garage at the Sorby household. Luckily, they have a lift, making the install a lot easier. At the beginning of most new projects, there is a curiosity factor. We lifted the Saleen in the air and then laid out the piping underneath it to try and make heads and tails of it all. Our first thought was what did we get ourselves into? But that was quickly erased when we started turning wrenches and bolting on the pieces. The big picture becomes quite obvious once it starts to come together. Thankfully, this system does not require the addition of a K-member and A-arm setup like some of the Two-Valve and Four-Valve modular turbo combinations.
A Turbonetics 62mm turbocharger takes center stage in the front of the engine compartment. Its lavish looks detract from the rest of the system, which includes stainless steel exhaust piping, a Turbonetics Evolution wastegate, and a high-flow air-to-air intercooler, among other things. We also enjoyed the fact that there was no cutting required to install the system. The final product is both good looking and functional.
When the housing is too small, there is too much backpressure and the gases escape past the wheel without turning it. If too big, then the engine cannot fill the exhaust housing with enough hot gases to spin the wheel. It is a delicate balance, and Hellion worked with Turbonetics to build the proper size turbo for this kit.
The exhaust housing and exhaust wheel are responsible for turning the impeller. The exhaust housing is sized to properly spin the impeller using expanding exhaust gases (thermal expansion) and turn the exhaust wheel.
Billy Sorby had big plans for the Saleen in the near future, so he decided it was best to upgrade the fuel system (see Fuel Requirements sidebar) to something that will handle a lot more horsepower than the turbo system was capable of producing. He added a twin Ford GT fuel pump assembly from JPC Racing, as well as a set of 60-psi injectors. Other modifications included a pair of Ford Racing Performance Parts shorty headers, a Centerforce clutch, and a lightweight flywheel. Spetter recommended an adjustable boost controller for this combination, and the knob was mounted near the wastegate. More power is now only a twist away. Sorby added a mixture of C16 and 93 octane pump gas to the tank as an insurance policy for the dyno pulls. A set of Autolite spark plugs that were one heat range colder than stock were also used.
Out of the box, the Hellion tossed 11 psi of pressure into the Three-Valve engine, and it made an impressive 487 rwhp and 492 rwtq. Spetter moved the boost controller up a few clicks, and the difference was a few pounds of boost, placing peak boost at around 13.7 psi. That little upgrade increased output to a lofty 521 rwhp and 497 rwtq. We were stunned at the crazy power numbers and aggressive torque curve.
As impressive as it was, Sorby wanted more and even told us, "I didn't trailer this car to the dyno for nothing." Spetter obliged, and the result was a maximum reading of 17.89 psi, while corrected horsepower shot up to a sick 570 rwhp and 561 rwtq. When looking at the uncorrected numbers, the dyno read 604 hp at the rear tires. At this point, Spetter felt the turbo was at its limit, and, more importantly, he was concerned about the engine since it was 100 percent stock. It was on borrowed time, and while bragging numbers are fun, a blown engine deflates the good mood.
Spetter recommended that Sorby swap in a set of Autolite spark plugs that are one heat range colder. | 
A Turbonetics Evolution wastegate is used to bleed excessive exhaust gases. The wastegate mechanically monitors boost levels and maintains a consistent maximum boost. When a predetermined pressure is achieved, it bleeds off the exhaust gases to maintain that pressure. The turbo will reach that maximum pressure level in low-altitude and high-altitude conditions as the wastegate will compensate for more or less exhaust gases needed to spin the turbo to the desired boost output. | 
Like the centrifugal blower, the turbocharger relies on engine oil to lubricate its internal components. Oil feed and return lines are virtually identical to the blower setup. |