The sinister black Trans Am GTA on these pages has been given a hardy dose of SLP parts. Go-fast items such as cold-air induction, larger intake runners, free-flowing exhaust, and a hot computer chip transform the already healthy 5.7-liter V8 into a lusty hairy-chested performer. Times of 0 - 60 mph drop by over a second to 5.6 seconds, while quarter-mile runs of 14.1 seconds at 98.8 mph are gear-for-gear identical to those of a new L98 Corvette.
The basis behind the SLP parts is air-flow management. Any high school auto shop student knows it takes air, fuel, and spark to make horsepower, but only the right combination of all three will improve a car’s performance. The equation is more compli-cated by the use of computers to control everything in a car from ignition timing to fuel flow. So no longer can the shade-tree hot-rodder merely shop the swap meets for a trick camshaft or high-rise intake manifold. Fortunately, the parts we refer to have been developed by SLP Engineering (of Toms River, New Jersey) to significantly boost both torque and horsepower of ‘85-‘91 5.0 and 5.7-liter tuned-port-injected V-8s.
The SLP components are manufactured to General Motors original-equipment standards and sold through the GM Performance Parts catalog. Any GM dealer can order the parts and even will install them for you if you don’t like getting your hands greasy. It seems too good to be true, but the SLP parts also have recieved federal emissions certification (limited in California to off-road use only). Which means you won’t break into a cold sweat whenever a highway patrol car pulls alongside at a traffic light.
The details of the SLP parts are as follows:
The 5.7-liter V-8 engine in our test car was mated to a four-speed automatic transmission. Although peak power with the SLP equipment installed only climbs from 240 horsepower at 4400 rpm to 266 at 5000 rpm and peak torque increases from 340 foot-pounds at 3200 rpm to 355 at 3700 rpm, there’s far more to the improvement than strictly data panel numbers. In real-world terms, the engine feels as if it grew another 75 cubic inches in displacement, because at 5500 rpm, it’s producing 50 horsepower and 50 foot-pounds of torque more than stock. The usual flat spot in acceleration above 3000 rpm is gone, replaced with a sharply escalating power curve that keeps the charge fast and furious well past the stock Pontiac motor’s useable limit of 4500 rpm. Any time, any place, there’s an immediate blast 0f power that’ll even light the tires from a 25-mph roll.
In 1992, things will get hotter yet. Pontiac will offer a limited run of 250 bright-red Firehirds stuffed with heavily modified 360-horsepower 5.7-liter V-8s. Backed by a Corvette ZF six—speed plus 17-inch wheels, the “Firehawk” special is a true ZR-1 chaser. Quarter-mile times are in the low 13s, and prices will start at $39,995. Our drive in an early prototype of the Firehawk was reminiscent of trying to tame a NASCAR racer — nothing but go-sideways power at any speed. Impressive. Awe-inspiring. Scary. We can’t wait."
TECH DATA
Model ........ Pontiac Trans Am SLP
GENERAL/POWERTRAIN
Body Style ........ 2-door, 4-passenger
Vehicle Configuration ........ Front-engine, rear- drive
Engine configuration ........ V-8, OHV, 2 valves / cylinder
Engine displacement ........ 350 c.i. / 5733 c.c.
Horsepower, hp @ rpm, SAE net ........ 266 @ 5000
Torque, Lb.-ft. @ rpm, SAE net ........ 355 @ 3700
Transmission ........ 4-speed automatic
Axle Ratio ........ 3.23:1
DIMENSIONS
Wheelbase, in/mm ........ 101.6 / 2566
Length, in/mm ........ 195.2 / 4959
Curb Weight, lbs ........ 3343
Fuel capacity, gal ........ 15.5
CHASSIS
Suspension, f / r ........ Independent / live axle
Steering ........ Recirculating ball, power assist
Brakes, f / r ........ Vented discs / drums
Wheels ........ 16 x 8.0, cast alloy
Tires ........ 245/50-ZR16
PRICE
Base Price ........ $19,500 (est.)
Price as tested ........ $21,800 (est.)
