Dubbed the Japanese Ferrari when it debuted in 1990 as a 1991 model, the Acura NSX is a "wish car" for many heavy-footed enthusiasts, this writer included. The wind-splitting dream machine is pure performance with a stout VTEC-enhanced 270-hp V6 mounted amidships, a smooth five-speed manual and 11-inch discs front and rear. The high-tech aura of the car can be seen in the sheet metal and beyond. Aluminum is the weapon of choice for the chassis, body panels, sub-frames, suspension a-arms, coil springs and anti-sway bars.
The first gen NSXs (1991 to 1996) are the most abundant and affordable examples but the gene pool is only about 6,800 samples deep, so these seductive sport coupes are rare gems indeed. The prices of used and abused early 1991 and 1992 models have come down to where mere mortals can afford them. The "used" check in from $27,000 to $30,000 while the "abused," higher-mileage models can be had for as little as $20,000; and as usual, the key to finding the bargain is timing.
When it comes to boosting, the NSX turbo freaks have had it hard. The midship engine configuration makes turbo placement a tough cookie to crack. There have been twin variable-vane turbo systems with the hairdryers placed beneath the engine. The challenge here is oiling the center section(s), which end up below the oil pan making regulating the flow of oil difficult. Also intercooler placement can be a nerve-wracking, knuckle-busting process, with some systems putting the chiller in the rear trunk area.
Gerry Johnson is a machinist/enthusiast turned car builder/tuner and his boosting odyssey led to the creation of Performance Autoworx in Modesto, Calif. Johnson was in the market for an NSX and found the one in Dallas, Texas. He drove it home and installed a set of lowering coils and some Work wheels he had waiting in the wings.
"After owning many fast cars in the past (five 300ZXs, an '89 slant-nose Porsche) I was a little, actually a lot, disappointed with the power of the NSX," relates Johnson. "So I began the search for power-turbo power, that is-and found one company that was making a twin setup for the NSX using Aerodyne turbos. I bought one and installed the kit and was pleased with the increase, but after a few months, 75 extra ponies was no longer enough. So I added some larger Aerodynes, pushed the boost from 7 psi to 10 psi and added an Electromotive TEC-II for management. This was too much for the turbos; they were killing bearings almost instantly even through they were rated to 15-17 psi. After burning up seven turbos and $7,000 in the course of a few months, I had enough and that's when this NSX adventure really begins."
"I decided to build my own turbo kit using a Garrett turbo," says Johnson. "To simplify things with the plumbing of the system I decided to go single and I then set off fabbing the piping and so on. I also knew I had to build the engine to make the power I was aiming for."
Bell & Gaines Racing fitted the C30A with cylinder sleeves and Johnson fortified it from the crank on up with a set of 9.5:1 compression JE slugs; stock titanium rods machined and bushed to incorporate floating pins and ARP fasteners on call at every turn: rods, main studs, head studs, etc.
Johnson also worked his magic on the V6's cylinder heads. He un-shrouded the pockets and worked the short side radius just past the seats to enhance flow around the valves and then matched the intake ports and polished the runners. The heads were assembled with Ferrea valves, Crower titanium retainers, Crower keepers and R&D double spring valve springs.
To address any possible oiling issues, Johnson upgraded the oiling system with a billet oil pump gear designed to increase flow 30 percent, constructed special baffling in the pan and added a Fluidyne oil cooler.