This Blown 1998 Pontiac Trans Am LS1 went from sidelined project to 9.90s in just 2 1/2 Months
It certainly isn't uncommon to read about hobbyists rescuing stalled Pontiac projects from a previous owner and turning them into quick race cars, hot street machines, or coveted show winners. It is, however, somewhat new to HPP to have this occur with a late-model Pontiac--one that's just 7 years old.
Nevertheless, that's exactly what happened with this '98 Trans Am. Current owner Kevin Polchan, a 42-year-old mechanic (retired) and moderator on LS1Tech.com, was on the prowl for a smart-looking LS1-powered stormer that could surprise would-be competitors by combining a subtle appearance with tire-shredding performance. After owning a string of LS1 rides, including multiple Camaros and a C5 Corvette, Kevin was anxious to apply his 25 years of racing experience and the knowledge gained on those vehicles to something new. "I was looking for a car to have fun with at the dragstrip, and it's hard to beat the aggressive look of a '98-and-up Trans Am with a WS6-style hood," he says.
It just so happened that Kevin's friend John Skiba had begun a buildup on a black '98 T/A and had made it as far as upgrading the LS1 inter-nally in the hopes of installing a supercharger. Then, as is the case with so many good intentions, the project slowed and John lost interest.
Recognizing the opportunity, Kevin drove to Chicago, where he grew up, to cut a deal with John. He traded $12,000 for the 34,000-mile F-body and trailered it back to his Knoxville, Tennessee, home in early March 2005. "I drove it 100 feet off the trailer into the garage and then pulled out the entire stock driveline, A/C, brakes and interior," Kevin says.
John had built the engine prior to Kevin's purchase, retaining the stock block. He fitted it with forged Wiseco pistons wrapped in rings by the same company for durability and to drop compression to a more blower-friendly 9.5:1. The stock crank and LS1 rods were retained, but the former was polished and the latter had ARP bolts added. Federal-Mogul fully-grooved main bearings and Clevite 77 rod bearings were to be cooled via the stock LS1 oiling system. An '01 hydraulic roller Z06 cam featuring 204/211 degrees duration at 0.050, a 116-degree lobe separation angle, and 0.525/0.525 lift with the factory 1.7:1 roller rockers was installed 1 degree advanced. The stock heads were ported by ET Performance (flow numbers N/A), stock 2.00/ 1.55 valves were retained, and an LS6 intake manifold was installed.
Leaving well enough alone inside the engine, Kevin bolted on an ATI-ProCharger D-1SC supercharger with an SDCE eight-rib, spring-tensioned drive system. Boost, to the tune of 13.5 psi, is forced though an OBX 12x22x4-inch intercooler that can be seen through the holes in the front bumper where the license plate cover and foglights used to be. The pressurized atmosphere is blown through a stock 78mm MAF and ported 78mm throttle body.