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.
The T/A rides on 15x4 and...
The T/A rides on 15x4 and 15x10.5 Bogart wheels wrapped in Mickey Thompson 28x7.5x15 tires and 275/50R15 drag radials.
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.
The Vortech V-1 T-Trim supercharger...
The Vortech V-1 T-Trim supercharger on the LQ9 6.0L engine has an upgraded reservoir, also known as a chill box, which forced Speed Inc. to relocate the battery to the trunk using a BMR battery relocation kit. The chill box has more water capacity than the "kit" unit, and therefore creates a cooler air intake charge and more power.
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.
A big Vortech V-1 T-Trim blower...
A big Vortech V-1 T-Trim blower makes more power than the usual V-9 G-Trim unit you see under the hoods of T/As. The 3.1-inch upper pulley aids in providing 16 psi of boost.
The A-pillar gauges from top...
The A-pillar gauges from top to bottom are fuel pressure, boost, and transmission temperature. To the right of the steering wheel is a 5-inch tach with a 10,000 rpm redline. All of the after-market gauges seen are from Autometer.
This '98 Trans Am was built...
This '98 Trans Am was built up to showcase an 800 cfm Vortech Supercharger, and then the original owner kept going, and going, and going, all the way to $80,000 of performance and custom mods.