A mere 11 years ago, fans of Pontiac rejoiced when Ed Hamburger of Street Legal Performance (SLP) joined forces with GM to create the Comp T/A package. The special edition Trans Am celebrated the 25th anniversary of BFGoodrich's Comp T/A line of performance tires.
Produced over a three-year span from 1995 to 1997, there were a total of only 164 Comp T/As made. All cars were shot in bright metallic silver and came loaded with factory options, including the 1SA option package and T42 Trans Am spoiler. Once SLP took delivery, it added a lightweight RTM composite hood with a cold-air induction; a performance air induction; 17x9-inch cast-alloy aluminum wheels; and a dark gray, 10-inch, center body stripe; along with the requisite BFGoodrich Comp T/A tires and a numbered dash plaque. Performance was brisk for the day with 300 hp on tap from the LT1 engine with 360 lb-ft of torque.
One such original Comp T/A owner is Bret Harwell, a food wholesaler from Forney, Texas. According to Bret, "I purchased the Comp T/A because it was a limited-edition Trans Am, and the color and Comp T/A stripes along with the wheels and Comp T/A badging made it stand out in a crowd. As car number 72 of a planned run of 200, it turned out that this was the last of 72 Comp T/As produced for the '95 model year.
"After driving the car sparingly for the first six years, I really wanted to increase the performance of the motor. Rather than trade the '95 in on an LS1-based Firebird and build up that platform, I decided to build up the Comp T/A to meet my visual and performance goals. Since the market wasn't commanding a significant premium for used Comp T/As, I decided to reinvent the car into the most radical, LT1-based street Firebird possible.
Several requirements had to be met in the car build, including custom paint with lots of wild graphics; an LT1 engine with Dominion four-valve-per-cylinder heads; and finally, it had to be supercharged and capable of 1,000 rwhp. Once complete, I envisioned attending car shows, driving it on the street in nice weather, and making a pass or two on the quarter-mile in search of 9-second e.t.'s. After five years of modifications and over $100k invested, I have almost reached my goals.
Engine And Drivetrain - Following the removal and storage of the stock 5.7L LT1 engine, Bret commissioned Hans Feustel Racing Engines of Fort Worth, Texas, to build a 396ci LT1. In order to produce the power the owner desires, a stout block and heads that would flow monster amounts of air were required.
Dominion aluminum heads, produced by Arao Engineering, feature four valves per cylinder. Rather than the stock LT1 valve sizes of 1.94 intake and 1.60 exhaust, the Arao heads feature two 1.65 intake valves and two 1.40 exhaust valves per cylinder, or roughly 35 percent additional valve area. With a centrally located spark plug, modern combustion-chamber design, and huge ports, the heads flow an ungodly 389 cfm on the intake and 303 cfm on the exhaust with the optional Stage 3 porting specified.
Starting with a fresh GM LT1 block, Hans Feustal bored it 0.030 over and performed the necessary clearancing for the connecting rods on the bottom end and pushrod areas on the top end to support the stroker rotating assembly and cylinder heads, respectively. A Lunati Pro-Billet 3.875-stroke crankshaft and 5.85-inch rods were employed. Filling the 4.030-inch bores are custom 9:0:1 Ross forged pistons and JE chrome-moly piston rings. Feustel commissioned custom, billet, four-bolt, splayed main caps and blueprinted a Melling high-volume oil pump before assembling the short-block with Clevite engine bearings and ARP bolts.
A nasty Cam Motion solid roller with 265/265-degrees duration at 0.050 and 0.572/0.572 lift with Dominion 1.4:1 roller rockers actuates the valves along with Dominion high-rev dual valvesprings. At the time of purchase, no intake manifolds were available, so a custom sheetmetal EFI intake was created by Hogan's Racing Manifolds to mate with the Dominion heads on the LT1 block. Following the build, the engine was dyno tested, where it proceeded to extract over 600 hp and 550 lb-ft of torque without the aid of a blower.
To reach the stated horsepower target, a ProCharger D1X supercharger system was purchased, and the task of mounting the blower and integrating the computing system fell into the capable hands of Keith Lohse of Real Performance Motorsports (RPM). In addition to mounting the supercharger, a Griffin intercooler was purchased and was seamlessly integrated into the front of the car. With a blower capable of generating 35 psi on the kill setting, a complete 3-inch blower/intercooler piping system had to be fabricated, and an 811/42-inch pulley for the crank and a 311/42-inch pulley for the blower were sourced from ATI to ensure the boost reached the target of 23 psi.