Politicos and silver-screen adulation junkies have long recognized that the capacity for reinvention is the cornerstone of longevity. The principle obtains equally in the automotive realm, where product planners have been repurposing powerplants, vehicle platforms, and catchy monikers since before Henry Ford developed his ill-advised predilection for liebfraumilch and lederhosen.
For a modern exemplar, one needs look no further than GM's many-splendored "Gen. III" engine family. Since sloughing off its caul between the hydroformed frame rails of the all-new 1997 Corvette, this endlessly renewable performance resource has seen duty in a wildly divergent range of applications, from spec-race machines to workaday pickups to the suppository-shaped Australian cutter known popularly as the 2004 Pontiac GTO. Individual performance buffs have taken a particular shine to the performance-tuned LS1 variant, making the 1998-2002 F-Body perhaps the most widely modified domestic vehicle platform since the days of the 4.9-liter (aka "Five-O") Mustang.
One trend currently in particular vogue among higher-echelon LS1 tuners is that of augmenting engine displacement through the use of bored-out blocks and long-stroke crankshafts. As we typically adhere to the time-honored "bigger is better" maxim in matters of vehicular motivation, it should surprise exactly no one that we recently fell hopelessly in thrall to the brutish charms of Aaron Thames' 1999 Trans Am. Stuffed to the gunwales with seven liters of Gen. III firepower, it's the sort of perception-altering experience one never quite gets over.
A previous owner of two LT1 F-Bodies, Thames was appalled to discover just how poorly the old iron-block thumper fared against its high-tech successor in contests of straight-line acceleration. "I raced a stock LS1 with my modified LT1 car and was handed my backside, so I purchased [the '99] new," he says. "I knew immediately I was going to upgrade the car."
His bruised ego now on the mend, Thames immediately set about crafting his own vision of the ultimate F-Body escape module. The transformation began on a reasonably modest scale, consisting of a "Stage II" head-and-cam package from Houston-based speed-peddler Motorsport Technologies Inc. (MTI). No shrinking violet, the setup was good for 10-second ETs at almost 130 mph with a supplemental snort of nitrous oxide.
Still, stupefyingly quick F-Bodies are increasingly the norm in Texas, and Thames was not about to let his car fall behind the ever-advancing engine-technology curve once again. For the second round of upgrades, MTI prescribed its burly 422-cube LS1 stroker engine, versions of which have proved capable of punting a properly prepared F-body through the quarter mile in under 10 seconds. The foundation of the package is a re-sleeved LS1 block, into which the MTI techs stuffed a street-oriented custom-grind hydraulic cam, forged Lunati crankshaft, and a set of Wiseco 11.25:1 forged pistons. A pair of extensively ported LS6 cylinder heads with upsized valves repose thereon, while MAC intermediate-length headers ("the old-school kind," reports Thames) and a 3-inch Corsa cat-back channel the combustive leftovers abaft. In the unlikely event the big engine can't get the job done on its own, a TNT wet nitrous system plumbed into the ported throttle body administers a 150-horsepower coup de grace.
Output is predictably vast. Although Thames hasn't had an opportunity to track-test the new combination as this is written, he prophesies high-9-second ETs "on the bottle" given adequate traction. That sounds perfectly reasonable considering that the car recently put 505 SAE-corrected horsepower to the rollers at the MTI dyno shop (675 with the conservatively rated nitrous system flowing).
Upgrades to the remainder of the drivetrain are rather less drastic, comprising a McLeod twin-disc clutch and a KTRE 12-bolt rear end housing factory-issue 3.42 gears. The stock 6-speed trans and driveshaft remain, though Thames is understandably reluctant to provide a forecast for their continued wellbeing. "The first time I really hook up on the slicks, well, that'll probably be about it."
To bring the TA's visual presentation into concinnity with its otherworldly power output, Thames had Rudy Gutierrez at 911 Collision in San Antonio strip away the factory black paint in favor of a sulfurous shade of orange called, simply, "Sunset Pearl." (We're thinking "Satanic Tangelo" is more like it.) The resulting look is equal parts roadgoing supernova and Bikini-atoll A-bomb test--just the thing for striking fear in the hearts of impetiginous Vin Diesel aspirants in pavement-scraping Civic hatchbacks.
Incredibly, Thames avers the car comports itself with the civility of a stocker in everyday driving. "I told MTI I wanted the most streetable 422 they could build, and that's what they gave me. I drive it to work on a regular basis. It idles smooth, and I've never had any issues with overheating, even in bumper-to-bumper traffic."
Even the interior presentation bespeaks an emphasis on the quotidian. Forsaking generally accepted speed-junkie logic, which dictates that cars in this performance stratum be approximately as comfortable as a barium enema, Thames' chose to preserve virtually all of the TA's factory-installed luxury spiffs, right down to the HVAC system, Monsoon audio rig, and a multiplicity of power assists. (He has, however, yanked the back seat since our photo shoot.) Safety equipment? Yeah, there's some of that.
"I run at RCR [River City Raceway], which is an IHRA track," explains Thames. "I'm really not consistent enough yet to run at a bigger track. Besides, if I added a roll cage it wouldn't really be a street car anymore."
But isn't there at least some sort of tech-in process?
"Yeah, of course. They say, 'You got a helmet?' That's pretty much it."
Kind of sounds like our job interview.
If J. Robert Oppenheimer designed...
If J. Robert Oppenheimer designed a road car, chances are it would look something like this. Of the numerous descriptors that spring instantly to mind, "subtle" is not one.
Accelerative motivation is...
Accelerative motivation is provided by a 422-cube MTI stroker engine worth a very civilized 505 rear-wheel horsepower naturally aspirated, and around 675 on the bottle. Transparent MTI airbox lid adds a piquant finishing touch.
Thanks to a wheel-and-tire...
Thanks to a wheel-and-tire combo that is heavily skewed toward full-warp dragstrip sorties, Thames' TA is no threat to Porsche pilots when the road starts to kink. Power Slot front rotors help the car divest itself of 130-plus mph of trap speed.
On those occasions when comprehensive...
On those occasions when comprehensive demoralization is desired, Thames can unloose a fortifying 150-horse snort of nitrous directly into the car's ported throttle body.
It takes a special brand of...
It takes a special brand of fatalism (not to mention a determinedly apathetic tech crew) to run 9-second ETs without the benefit of a roll cage. Nitrous-bottle-pressure gauge sprouts from the A-pillar like an enucleated eye.
|Car: ||1999 Pontiac Trans Am|
|Owner:|| Aaron Thames|
|Block: ||Re-sleeved LS1, aluminum|
|Compression ratio: ||11.25:1|
|Heads: ||Ported LS6 with Ferrea 2.08-/1.60-inch valves|
|Cam: ||Comp/MTI hydraulic roller, .612/.612 lift,244*/244* duration at .050|
|Pushrods: ||7.4-inch Chrome moly|
|Rocker arms: ||Stock 1.7|
|Pistons: ||Wiseco forged|
|Rings: ||Childs & Albert|
|Crankshaft: ||Lunati forged|
|Rods: ||Lunati billet|
|Throttle body: ||Ported stock|
|Fuel injectors: ||Ford SVO, 30-lb./hr.|
|Fuel pump: ||Stock|
|Engine management: ||Stock GM PCM with MTI tuning|
|Power adder: ||TNT single-stage, 150-hp wet nitrous system|
|Exhaust system: ||MAC 1.75-inch headers with custom cut-out, Corsa 3-inch cat-back|
|Transmission: ||Stock T56 6-speed with Pro 5.0 shifter|
|Clutch: ||McLeod twin-disc|
|Driveshaft: ||Stock aluminum|
|Front suspension: ||Stock with Suspension Techniques springs|
|Rear suspension: ||Tokico adjustable shocks, Suspension Techniques springs, Lakewood lower control arms, MAC subframe connectors, right rear air bag|
|Rear end: ||KTRE 12-bolt with 33-spline axles, GM 3.42 ring and pinion|
|Brakes: ||Power Slot slotted front rotors, stock rear discs|
|Wheels: ||Weld Draglites, 15 x 3.5-inch (front)/16 x 9-inch (rear)|
|Front tires: ||Mickey Thompson ET Fronts|
|Rear tires: ||28x10-16 Hoosier drag slicks|
|Fuel octane: ||93 (naturally aspirated)/104 (with nitrous)|
|Power:||505 NA, 675 with Nitrous|
|Current mileage: ||73,000|
|Miles driven weekly: ||Approximately 300|