The 16-second timeslip handed to you through the window of your Cavalier is fast enough if your garage includes Mom's Taurus and Grandpa's S10. It's all about your frame of reference.
The contents of Chris Johnson's garage look like he shook a month's worth of feature cars out of our magazine and threw in a cover car from Hot Rod for good measure. Therein sit an SC 300 turbo, Silvia, Supra and Camaro Z28 with a stroked 396, replacing various past 'Vettes, and a Grand National.
Short of being a jet jockey, Chris' frame of reference couldn't be any more distorted. His definition of fast enough, for now anyway, is a 940-wheel-hp Supra.
Of the four cars featured on the cover, Chris, the proprietor and sole employee of Performance Motorsports in Austin, Texas, built three of them. Supras comprise 80 percent of his business, which supplies the extensive product knowledge that specialization provides. Only the racecar was screwed together by hands not attached to Chris' arms.
He offers us his personal car, the weakest horsepower link of the group, producing a paltry 940 hp. Pathetic this, only three and a half times stock power output.
While some Supra guys acquire equipment designed to make their cars stop and turn, most invest in flat-earth-consuming performances duplicated by only the very quickest and fastest street cars on earth. In fact, the turbo Supra community has more in common with American muscleheads than import canyon carvers.
Although Supras have been known to turn fast lap times, it's their battle-ax solution to automotive domination that identifies them with cars like Vipers, 'Vettes and slick-straining Mustangs. In other words, most MK IV Supras with EVO MR price tags poured into their parts are good at the following: car showing, dynoing, drag racing and, it's been rumored, putzing around with turbo Hayabusas on lonely stretches of tarmac.
Three of those four pursuits require wanton power production, an expensive desire that Chris is happy to indulge for customers and, when he has time, for himself.
The stock Supra bottom end has proven itself reliable to power levels that trump a modern Formula One car. When building the lump for his '95 Supra, Chris blueprinted a stock bottom end with the exception of Carrillo H-beam rods, which are lighter and stronger than the forged rods they replace. These add a measure of security for a car whose destiny includes repeated street pounding, bouts with the rev limiter and near single-digit quarter-mile passes.
After ditching the stock baby turbos, Chris, who works closely with Boost Logic, installed the company's single-turbo conversion kit. The Boost Logic exhaust manifold is TIG-welded, 321 stainless material, and locates the Boost Logic/Precision T74 turbocharger fitted with a GTQ exhaust wheel and .81 A/R housing. Ambient air, usually warm and muggy, gets sucked into the 2JZ's pressure chambers via Boost Logic's 4-inch aluminum intake pipe, coated to resist thermal contamination from the glowing hot, football-sized turbo.
Air blown out of the snail winds through 3-inch, thermally coated aluminum intercooler plumbing, where it is cooled by a GReddy three-row intercooler. Treated air is transported through 2.5-inch aluminum piping to a huge 85mm Accufab throttle body.
Above 800-wheel hp, the stock intake manifold becomes a restriction, an issue solved by the fabrication and installation of a large-plenum, polished aluminum intake manifold. Compressed air is muddled with fuel provided by 1000cc injectors from RC Engineering mounted in an HKS fuel rail.
Occasionally, extra molecules of oxygen arrive from a single-fogger 50-shot wet kit from Nitrous Express, which on big turbo cars like this one, often provides more of a horsepower increase than the designation suggests. The geysers spraying into each cylinder are provided fuel by two Walbro 255-lph fuel pumps, through braided lines, Aeroquip AN fittings and an Aeromotive -10 fuel filter and pressure regulator.
Tubing 4 inches in diameter disgorges exhaust from the back of the T74; both the downpipe and exhaust are sourced from Boost Logic's product line. TiAL's 44mm wastegate defines maximum boost levels, which are otherwise controlled by the stand-alone AEM EMS. The EMS, with a HKS DLI Twin Power Ignition and FJO wideband, allows for onboard fine-tuning.
Large power gains can be realized from reworking the top end of the 2JZ, and Chris has invested significant energy there. All the factory-cast surfaces were ported and polished in-house, and 1mm oversize valves are fitted to expedite movement of gases in and out of the cylinders.
Aggressive cams are a crucial ingredient in the high-horsepower Supra stew, here addressed with 272-degree cams from HKS. These work against Crower springs and titanium retainers, helping the engine spin reliably to 7900 rpm.