Low-volume commemoratives have loomed large in the history of Pontiac’s high-performance Firebird Trans Am. Remember the black-and-gold ‘76 honoring Pontiac’s 50th birthday? How about the 1979 "TATA" (Tenth Anniversary Trans Am) or the 15th Anniversary edition of just five years ago?

Well, now there’s another one in 1989—marking two decades of Trans Ams. It’s a hotter version of the already potent top-line GTA, created for both the 20th birthday and pace car duty at the Indy 500. Its official name is a real mouthful— 1989 Indianapolis 500 Pace Car 20th Anniversary Pontiac Trans Am—so let’s just call it TATA II (say "tah-tah too").

- At first glance, this might seem just another latter-day performance car aiming for "instant collectible" status with nothing more than special trim, extra horsepower, and deliberately limited production in its favor. But TATA II is a little different. For one thing, it’s got a Pontiac soul but the heart of a Buick: the powerful 3.8-liter turbocharged V-6 from the recently deceased Regal GNX. For another, any one of the 1500 copies that Pontiac will screw together could, right from the factory, roll into the Brickyard and lead the CART cavalcade. As a division press release breathlessly observes, the 20th Anniversary T/A "meets every [Indianapolis Motor] Speedway performance requirement for pacing the starting grid without any mechanical or technical modifications."

In short, unlike previous production pace cars—including all those Trans Am specials—TATA II isn’t just a replica but the real thing. Says Pontiac chief J. Michael Losh: "When our Trans Am paced this event in 1980, we modified the car to meet track requirements by simply leaving off the air conditioning package. Now we have achieved the ultimate Trans Am to date . . . a completely stock car to pace these powerful racing machines!"

Fine, Mike, but only so many cars can pace a race, and you surely won’t have all 1500 TATA IIs at the track come Memorial Day, so just imagine the historical hysteria 20 years hence:

For sale—1989 20th Anniversary Trans Am. Mint. All-white, ground effects, turbo, air, full power, WS6, T-roof, camel interior. One of only 1500 built. Actual Indy Pace car. Must see to appreciate. $100,000 o.b.o.

On second thought, better make that five years hence. Far-fetched? Perhaps you’ve not heard what fools and their money have been doing to collector-car prices. But let’s stop borrowing trouble and look at the car itself. As mentioned, it’s based on the GTA package that’s been around since 1987 (five years after the current third-generation Firebird and Chevy Camaro arrived). Motive power is its chief distinction. Instead of a 5.7-liter V-8 with multi-port fuel injection, Pontiac drops in the sequentially injected Buick turbo V-6 from the tire-smoking GNX. The GNX vanished along with this engine when the 1978-vintage rear-drive Regal became a front drive GM-10 for ‘88 (as did Pontiac’s Grand Prix and the Olds Cutlass Supreme).

"Drops in" is a bit misleading, as this swap was something less than straightforward. Though the Buick V-6 is a 90-degree engine like the 5.7L V-8, it was too wide across its cylinder heads for the Firebird engine bay. The solution was to substitute the more compact heads from the related 3800 V-6 that sits transversely in many of GM’s full-size front-drive cars. This slimmed the turbo mill two inches, enough for it to fit (like the V-8, longitudinally, as in the GNX).

One other major problem was unwanted engine vibration. This hadn’t been apparent in the Regal because of its rubber-isolated body-on-frame construction, but reared its ugly head in the stiffer, unit-body Firebird. Engineers tried a variety of dampers and engine mounts before settling on flexible couplings between the exhaust manifolds and the exhaust pipes. These gave acceptable results, though there’s still work to do.

Has all the effort been worthwhile? On paper, yes. With a rated 250 horsepower and 340 pounds/feet peak torque, the blower Buick is stronger than the 5.7 V-8 by 25 horses and 10 lbs/ft. More importantly, it lightens the GTA by some 125 pounds, leaving curb weight at around 3400. Pontiac mandates the same four-speed overdrive automatic transmission for both models. Despite this, the 20th Anniversary T/A is claimed to do 0-60 mph in a sizzling 5.4 seconds and the standing quarter-mile in under 13—making this one of the fastest showroom Trans Ams since the hallowed ‘69 original.

It may even be a bit quicker still, as some estimates put the Buick engine’s actual horsepower at closer to 270. Though academic in America, top speed is reportedly in the region of 155 mph, some 30 mph above the GNX’s. The explanation lies in the superior high-speed stability of the more aerodynamic Firebird body, and the fact that Pontiac felt no need for the speed governor that Buick used to keep the boxy Regal from literally taking off at three-figure speeds.

Unfortunately, neither we nor anyone else at this writing can verify TATA II’s performance, this being a mid-year model that Pontiac hadn’t yet released for testing. But even if it’s no faster as a practical matter, removing 125 pounds from the nose-heavy GTA certainly can’t harm handling, and there’s more than enough torque on tap for impressive stoplight getaways.

Except for larger front-brake rotors to handle the extra muscle, the 20th Anniversary is pure GTA. This means the familiar 101-inch-wheelbase F-car chassis with stiff-riding WS6 sports suspension; wide, 16-inch-diameter lacy-spoke alloy wheels wearing chunky P245/50 performance radials, now of the ultrahigh-speed Z-rated variety (good for over 149 mph, versus the previous 130-mph V-rated rubber); limited-slip differential; and power all-disc brakes and recirculating-ball steering.

Naturally, you get the mean-looking GTA/Trans Am "aero" exterior with sculptured "bottom-breather" nose, low-riding front airdam with integral fog lamps, skirted rocker panels, and prominent "tea-tray" hatch lid spoiler. Other standards inherited from the GTA include air conditioning, AM/FM cassette stereo with graphic equalizer, cruise control, tilt steering wheel, power windows and door locks, and shapely, articulated front bucket seats with inflatable lumbar support and thigh bolsters—all very plush and a far cry from ‘69.

Echoing that original T/A, the 20th Anniversary edition comes only in white. No broad dorsal racing strides, sad to say, but you do get a set of owner-applied Indy 500 Pace Car decals for doors and windshield, plus "Turbo Trans Am" badges, cloisonne’ Indy Speedway logos on the front fenders, and special 20th anniversary emblems on nose and sail panels. Inside it’s any color you like so long as it’s camel (light tan).

- Pontiac doesn’t say so, but we’d guess all TATA IIs will be equipped pretty much the same way, if only for convenience—and maybe better quality control—at the Van Nuys, California Camaro/Firebird assembly plant. The sole exception is the optional T-bar roof. Unlike the normal GTA, which gained an alternative notchback-style hatch treatment last year. the 20th Anniversary comes only in familiar "glassback" form, this to accommodate the T-roof that will— again quoting that press release—be fitted to "all Indianapolis Pace Cars for use at the Speedway and in associated civic events prior to the actual race." This doesn’t mean that the T-roof TATA II you stumble across 20 years from now will necessarily be one of the official race-week cars, though it will increase the odds—and no doubt the asking price.

Pontiac’s asking price is about $²⁵,000—quite a bargain, all things considered. But with only 1500 copies and close to 3000 Pontiac dealers, you’re going to have move fast if you hope to own one. In fact, it may already be too late by the time you read this. But then, limited editions have always been showroom draws designed to sell out fast, and TATA II is sure to be no exception.

Any Pontiac fans offended by that Buick engine should recall the use of Chevy power in the few Firebirds that actually competed in the Sports Car Club of America’s original Trans American series, which is what started this whole business. Back in 1968, Pontiac’s smallest V-8 was a 326, too large for the maximum 305 cubic inches the rules allowed. But that didn’t stop Terry Godsall, a cagey Canadian who dropped in the high-winding 302 small-block from Chevy’s then-new Camaro Z-28 and told officials it was a Canadian Firebird. While some Canadian Pontiacs used Chevy engines, Firebirds didn’t, but SCCA bought the story anyway. Jerry Titus did the driving, but scored no major wins. SCCA caught on when Godsall updated his car to ‘69 specs, but they let him run after making him put a ‘68 grille on the ‘69 body. Again, though, success was elusive.

In fact, Pontiac’s first Trans-Am victory didn’t come until 1972, when the series was far less competitive. But it didn’t matter much by then: The very special Firebird with the racy name was already a performance legend. And its legend would grow even through the dark and dull Seventies as Pontiac wisely persisted with the Trans Am, keeping faith with enthusiasts while most other makers abandoned them. Pontiac, too, lost its way for awhile, but has since come roaring back—on the street and in the showroom — by again offering spirited performance in the tradition of the great ‘69 T/A.

As the newest and most sophisticated expression of the Trans Am idea, the 20^th Anniversary edition not only symbolizes this return but decisively reaffirms Pontiac’s entire performance heritage. That these 1,500 T/As will be lovingly gathered in seems as certain as their fast sellout. The only real questions are what they’ll go for new, and how values will fare in the future. While your guess is as good as ours on those points, it seems safe to say that, "instant collectible" or no, TATA II will be stirring hearts and souls for a good long time.