A Brief History of SLP & What Led to the Fifth-Gen ZL/Panther Camaro

From the late ‘80s through the dawn of the new millennium, Street Legal Performance (SLP) made its bones up-gunning GM’s F-body Chevy Camaro and Pontiac Firebird. Credited with reviving and energizing the pony cousins fabled performance nomenclature like Chevy’s Super Sport (SS) and Pontiac’s WS6 and Ram Air badges, SLP is credited with the parts development/manufacture and the assembly of over 50,000 SS/WS6 cars from 1996-2002. SLP’s main claim to fame, however, was the Firehawk-a moniker to which fourth-gen Firebird fans the world-over still salute in praise. Hatched in the swan song years of the third-gen Firebird, SLP’s Firehawk Formula/TA featured unique styling cues and came equipped with a myriad of standard/optional SLP performance parts. The Firehawk is duly-noted as being one of the best-performing and fiercest examples of Pontiac’s fiery phoenix.

GREATER-GALLOPING GOAT: 2004-2006 421/455HP BOBCAT GTO PERFORMANCEPACS

Even after the fabled Firebird spread its wings for the last time, SLP once again embraced the Excitement Division’s great performance history by offering two upgrade packages for Pontiac’s new Holden Monaro-based GTO. Emulating the great Bobcat Pontiacs from the ‘60s and early ‘70s, which were hopped-up by Ace Wilson’s Royal Pontiac Dealership in Royal Oaks, Michigan–SLP’s homage consisted of the 421/455HP Bobcat PerformancePacs. Denoting crank horsepower instead of engine “cubes” like back in the day, The Pacs were a specific grouping of tried and true SLP performance componentry for use on both the 2004 5.7L LS1s and ‘05/’06 6.0L LS2 cars.

The 421HP Pac included a 160-degree thermostat, a high-flow air filter, SLP’s Loud Mouth II S/S cat-back exhaust, a custom PCM tune and a pair of “421 HP Bobcat” fender badges. Upping the ante and the cost for the 455-horse package added a 25% harmonic balancer/under-drive pulley, long-tube ceramic-coated headers flowing through a PowerFlo X-crossover and high-flow cats, the raucous Loud Mouth I exhaust and increased valve lift from SLP’s 1.85 ratio Rocker arms – with an appropriate tune and badges.

As with all SLP-enhanced cars before them, Bobcat 421/455HP-equipped ’04-’06 GTOs are known for squeezing even more power and performance out of their already impressive factory fitments. It was obvious that whatever hi-po machines GM had in the works for the future, SLP was ready and waiting.

THE HAWK FLIES AGAIN: 2008/’09 G8 GT/GXP FIREHAWK

Although the short-lived Aussie-built GTO wasn’t to everybody’s liking style-wise, its performance prowess was never questioned. With that said, GM/Pontiac would soon provide another down-under wonder, this time in the form of the Holden Commodore-based G8. The 4-door performance sedan or (Saloon) in Aussie-speak, came in two variants for ‘08, the 3.6L V6-powered base car making 256-horses and the GT, with a six-speed automatic (6L80) wielding 361 hp/385 lb-ft of L76 V8 grunt. For 2009, Pontiac unleashed the ultra high performance G8 GXP, with an available Tremec TR-6060 six-speed manual, massive Brembo front brakes and the 415 hp/415 lb-ft C6 Vette-sourced LS3 V8. Unfortunately, the G8’s would be the last of Pontiac’s great performance flagships, but they would also provide SLP with a template to revive a storied nameplate and prepare for the return of an icon.

For 2009, SLP made the somewhat controversial decision (as far as Firebird owners were concerned), to revive the Firehawk name- applying it to an up-fitting-powertrain, suspension and appearance package for the G8. The initial setup for the GT included a TVS 1900 (1.9L) Supercharger, Blackwing cold air induction, SLP’s S/S PowerFlo exhaust with specific rectangular dual tailpipes, progressive rate springs that lowered the big sedans center of gravity by 1-inch in front and .08-inch in back, and gorgeous 19×8-inch open-faced 5-spoke graphite-finished/machined-edged wheels. Summoning the muscle car’s golden age, the hood and larger rear downforce-inducing spoiler were painted flat black–both could be painted body color–like the lower front grille surrounds and a quartet of OEM-grade chrome “Firehawk-supercharged” badges graced the front doors, trunk and engine bay. Completing the exclusive package were embroidered headrests/floor mats, a faux leather portfolio, interior numbered dash plaque, custom key fobs, and an SLP-logoed car cover.

Later, SLP added a naturally-aspirated version, with most everything minus the blower and even fitted a couple handfuls of GXPs with the supercharged package. Horsepower for the blown G8 GT Firehawk was a healthy 500-ponies at the crank, with 385hp for the natural breathers and pushing 600hp for the G8 GXP-based versions. Although the G8 GT/GXP Hawks were worthy successors, there were only 34 rare examples built, but according to David Hamburger, the true dual purpose of the Firehawk’s revival was about to be revealed.

David elaborates by referring to the G8’s and upcoming Camaro’s shared Holden-developed Zeta platform. It seems that the G8 Firehawks were a test bed for Chevy’s fresh pony car, allowing SLPs talented techs to work their magic before ever getting their hands on a 2010 model. David explained further that they were able to “get ready for the Camaro” with blower fitment on the LS3, suspension/chassis enhancements and wheel/tire and brake upgrades. All the work was done in preparation for what would soon become the ZL program.

Editor’s Note: Stay tuned to our follow-up story on the ZL/Panther Camaro!

About the author

Andrew Nussbaum

Pontiac possessed by Smokey and the Bandit at 6 years old, and cultivated through the '80s by GTAs, IROCS and Grand Nationals, Andrew hails from Queens NY and has been writing freelance for ten years.
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