1998 Pontiac Firebird Trans Am - Electricity In The Air
Bill Rochelle of Grove, Oklahoma, is an electrical contractor, so it isn't surprising that his '98 Trans Am adds a whole lot of electricity to car show competitions. "I was looking for a different car to show and drive," Rochelle told HPP. "I had an '02 SLP 35th Anniversary Camaro and just was not able to enjoy it like I wanted to. I decided to sell it and get a different one. My son was looking on eBay and came across a Trans Am. The more I looked at it and read about it, the more I wanted it."
This '98 T/A features $80,000 worth of performance and custom upgrades. It was designed by its original owner, Rodney Geffert, to promote his business, 7 Floors of Hell, and as a rolling showcase for a supercharger system provided by Gil Cormacy at Vortech, BMR suspension, and the talents of Speed Inc. "The car was put together for advertising, and the best of everything was used in its construction," Rochelle said.
Engine
Geffert contacted Speed Inc. of Schaumburg, Illinois, because his Trans Am was running a stock LS1 with a Vortech G-trim supercharger and he felt the need for more speed. Speed Inc.suggested rebuilding the stock LS1 with their upgraded Sportsman 348 package, which included a stock crank, Eagle H-beam connecting rods, Diamond pistons, and Stage 3 LQ9/LS6 Patriot Performance heads.
Geffert wanted even more horsepower, so Speed Inc. installed a Nitrous Express system to reach the next tier of performance, but the engine fell victim to fuel starvation resulting in a spun rod bearing (due to a fuel pump failure). Geffert then asked for a reliable 700 hp combo. "We applied our experience with GM Gen-III engines to build this Trans Am into a strip/showcar, while still allowing some streetability by using our Extreme 408 engine package," Larry Hamilton of Speed Inc. said.
Starting with the 6.0L LQ9 iron-block truck motor, Speed Inc. installed a 4.00-inch stroke Eagle 4340 crank that pumps Diamond -8.6 cc dished blower pistons and Billet 6.125 connecting rods. An SLP heavy duty oil pump augments a stock oiling system. Then Speed Inc. bolted on a set of hand-ported AFR 225cc intake runner aluminum heads with 72 cc combustion chambers. To move the valvetrain assembly, Speed Inc. used a custom CompCam with 224/232-degrees duration, 0.581/0.595-inch lift and a 114-degree LSA. Comp pushrods actuate stock GM 1.7 ratio roller rockers to compress AFR #8019 springs and open 2.08/1.60 titanium valves. The compression ratio is 9.5:1.
This Trans Am was converted to a Speed Density-based EFI system from Mass Air and uses HPTuner software, which allows it to handle over 15 psi of boost.
Air passes through a hand-ported 78mm-otherwise stock-throttle body, and fuel is provided by Motron 60 lb/hr fuel injectors. The intake manifold is from an LS6. The stock coil pack system feeds the current through MSD wires and NGK TR-8 plugs. Exhaust exits via Kooks 1.875-inch headers and a single 3-inch Y-pipe, into a single 3-inch pipe featuring one muffler and dual Mecham oval tips. A DMH electric cutout can be actuated to raise the decibel levels via open exhaust.
To twist the new engine, Speed Inc. contacted Rocky Mountain Competitive Research (RMCR) of Colorado Springs, Colorado, to provide the bracketry to replace the Vortech G-trim with a higher output T-trim head unit.
Michael Wendling of RMCR explained that the Vortech G-trim head unit is great for a stock LS1, but it has limitations when outfitted on a heavily modified motor. "Our upgrade kit was developed for Firebirds looking for more power than the standard Vortech H.O. kit can offer. It was designed by our head engineer and owner Mark McCallon, and is offered in two versions. The first kit consists of upgraded brackets and a Vortech V-1 T-Trim head unit, and the second has a Vortech V-7 YSi-Trim head unit. Rochelle's T/A has the first of the two.
"The reason for the upgrade is the V-9 G-Trim blower that comes with the standard Vortech kit flows 800 cfm, which is only enough for a stock motor with light mods. Once you do heads and cam or build a stroker motor, like Speed Inc. did to the LQ9 in the Trans Am, the G-trim head unit is actually holding the engine back. The Vortech T-trim head unit kit we designed flows 1,200 cfm-more than a 30 percent improvement over the G-trim. Our bracket kit bolts up to the same location as the standard Vortech kit. We use 31/48-inch ballistic grade steel for the brackets with CNC-machined spacers."
Wendling was pleased with the results. "We have made as much as 750 rwhp with the Stage 1 T-Trim kit," he said. Speed Inc. agreed. "Rochelle's T/A has 700 hp at the rear wheels," Hamilton claimed, having tested the Trans Am on his company's Dynojet dynamometer.
To build a bulletproof drivetrain, Speed Inc. had to address four main issues on the Trans Am in addition to the engine-fuel delivery, the transmission, the rear end and computer programming.
Hamilton told HPP that a 700 hp package requires dual fuel pumps to prevent fuel starvation. Speed Inc. replaced the T/A's in-tank fuel pump with an inline dual Walbro 255 lph/hr OE pump system. The first pump handles fuel delivery up to 5 psi of boost. Then the second pump activates and increases the fuel flow up to the supercharger's set limit of 16 psi of boost.
Remainder Of The Drivetrain
The Trans Am's stock trans and rear would expire at this extreme horsepower level. To upgrade the factory component limits, Speed Inc. installed a TCI SFI-approved flexplate, bolted a Yank 3,800-rpm stall converter to it, and installed a Finish Line Level 5 4L60E automatic transmission rated to 900 hp. It is mated to an aftermarket, 3-inch diameter steel driveshaft, which inputs to a Moser 12-bolt rear end featuring a 3.42 gear ratio, 1350 yoke, 33-spline axles and an Eaton posi unit. The shifter is stock.
Tuning
Speed Inc.'s final goal was to set 16-17 psi of boost into the computer programming of the '98 Trans Am. This proved quite a challenge. Hamilton told us the solution was to replace the factory wiring harness with one from a '99 T/A and to remap the engine parameters with HPTuner software. He said the '98 wiring harness is limited to a two-bar map sensor, but that the '99 harness allows a three-bar map sensor and custom tuning up to 30 psi boost. "It allows us to safely use massive amounts of boost with this Trans Am," Hamilton said.
Chassis Upgrades
The suspension is upgraded with a BMR panhard bar and torque arm, subframe connectors, and tubular upper and lower control arms. QA1 shocks are installed at all four corners. The brakes feature slotted/drilled rotors, but retain stock calipers.
Body And Paint
Geffert wanted his Trans Am to stop people in their tracks, so he turned to Mike Krug of Krug's Kustom Painting in St. Beloit, Ohio, for a custom spray. "We wanted to make the T/A look as good as it performed," said Krug. To do so, he logged 178 man-hours in transforming the F-body into a custom-paint show-stopper, starting with the factory color red and adding five separate graphics. "I did all of the design and paintwork, from the drawings to the final product," said Krug. "I wanted to make this Trans Am an incredible show car."
First, he added a custom Ram Air hood and a Mecham spoiler. Then he went to work on the graphics. To accomplish the look without using vinyl graphics, Krug told HPP he "masked off the first graphic, sprayed the colors, and then sprayed airbrush effects." Then he sprayed the painted graphics with clear, unmasked thecompleted graphic, and repeated the procedure a total of five times. "I used six House of Color paints on the base graphics: Orion Silver, Tangelo Pearl, Limetime Green Pearl, Black, White and miscellaneous candies and pearls for artworks," Krug said. A two-step BC/CC paint was used.
For the highly polished final result, Krug wet-sanded the entire car before any paintwork began. He also wet-sanded each of the graphics, and he sanded in between the applications of clear. Finally, he wet-sanded before the final polish on the car. "I was very pleased, considering the budget and time restraints," Krug recalled.
Conclusion
Is this 700 hp Trans Am street-friendly? "It is streetable, although it is not a car to be driven any great distance," Rochelle said. "It does not like pump gas and requires 104-octane fuel. This means that in the small town that I live in, I have to buy 110-octane in a 55 drum and mix it with 91-octane to get to 104. That being said, it does drive well and is not totally unruly on the street. It does not run hot or get difficult to drive."
Rochelle told HPP he has big plans for his Trans Am. "The car has been on ESPN, and it is my desire to work hard to bring it to an even higher level of quality. Since I have not owned it that long and with my busy schedule, I have not had it in any major shows yet. One of the first will be the Trans Am Nationals in Dayton, Ohio, in August 2007."
Rochelle's Trans Am combines the promise of electrifying performance with stunning looks. "I am sure that the intention was for my car to stand out at the shows. It was designed to get attention and I do believe it does that well."

Photo Gallery: 1998 Pontiac Firebird Trans Am - High Performance Pontiac Magazine



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