Like most tuners, Factor X started out with the basic upgrades and charted their performance. The crew first installed an ARC intake, Comptech headers and ARC exhaust. This setup yielded gains in the area of 30 rwhp. Due to the NSX's excessively tall second gear Factor X opted to use the NSX-R short gears and ring and pinion. The next step was pulling out the big horsepower guns by plugging in a Comptech Supercharger system. Factor X says, "After some custom tuning we were extremely happy with the results." The result being 368 rwhp. With the dyno rollers still spinning they decided, "like all speed junkies we thirsted for more. The next progression was to add a 60 shot of nitrous." While this was satisfying in the short run, the excitement quickly wore off. "After a few months we began to tire of refilling the bottle every other day. So we decided to look at other options."

Civic or Integra owners are virtually limitless in the performance parts department. However, it is another story for NSX owners. "During that time there were not many options available for the type of power we were looking to make."

Out of suffering comes ingenuity. It was from this situation and Factor X's desire for power that led to the development of its own turbo system for the NSX. Dubbed the FX500, they designed "a single-turbo system that produced in excess of 550 rwhp and 420 lb-ft." From 368 to 550-plus rwhp? Whew, happy ending, let's all go home now. Unfortunately, in the world of mechanics the tenet holds true that for every action there is a reaction.

Something that many first-time turbo-kit buyers have experienced the hard way is finding out the stock motor cannot support such a huge power upgrade. Not wanting to blow up even a single engine, Factor X knew they needed to rebuild the engine to withstand the power of the FX500 kit. Action, reaction. Once they were in the middle of the engine build, however, they realized they had "opened up a whole new can of worms." Reaction to the reaction.

To tackle the task they purchased three additional C30 motors (no easy feat and damn expensive, too) and began building them for boost. Mike Angel built the six-cylinder engine and machining was completed by Combination Motorsports of Las Vegas, Nevada.

Displacement was bumped from 3.0 liters to 3.2 liters by boring the cylinders out from 91mm to 93mm. Darton iron ductile sleeves house the Wiseco slugs. The NSX engine has a balanced crankshaft and Wiseco pistons and rings. The pistons are set at a boost-friendly compression ratio of 9.8:1. Connecting to the balanced and micro-polished crankshaft are Cunningham forged rods. Providing lubrication is an ARC oil pan and oil is cooled by a Setrab with Flex-a-lite Slimline fan.

Portflow of Carson, Calif., installed the valves, Ferrea double springs and Ferrea retainers after completing a mild port job. Expelling all fumes are Comptech headers and Magnaflow exhaust.Factor X built the transmission and assembled a custom Clutchmasters clutch. Ensuringthe NSX transfers all the power to the ground, Factor X designed and fabricated a set of heavy-duty CV joints to drive the rear wheels. For the chassis itself, NSX Type-R chassis braces and a Carbing Rear strut bar were used.

The next task at hand was to find a suitable engine management system for their turbo kit. A man by the name of Jon Kuroyama was there to save the day and helped adapt the HKS FCON V-Pro to the NSX system. They also relied upon the expertise of famous builder Tod Kaneko, who is just a phone call away in California.