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The Ram Air system used a production hood with a non-production airbox that routed air to the driver's side of the engine compartment. This housing used a stock WS6 air filter. Plastic ducting routed air to the LT1 throttle body. |
A tank for the air-to-liquid intercooler was mounted near the radiator core support. It held a mild glycol solution that was pumped into the cooling element in the blower manifold to reduce charge-air temperatures. |
Pontiac Special Vehicle Engineering built this Firebird Formula with a supercharged 4.3L L99 V-8 engine to test the performance potential of a smaller-displacement engine in a Firebird application. The steel-roofed Formula was an early '93 model, upgraded to WS6 specs. Though tough to see, the rear bumper fascia for the stock Formula has an empty spot where the passenger-side exhaust pipe would have gone. This car received a prototype version of the high-flow, single-outlet system that made it to production on the '98 WS6 Firebirds. |
The reason for choosing this less macho-looking system over a traditional dual-outlet system was clever and delightfully sneaky. A single outlet was positioned on the driver side because engineers learned that the EPA decibel test procedure always located the measuring microphone on the passenger side. The distance between the outlet and the mic was far enough that a substantially louder and freer-flowing exhaust system could actually pass EPA drive-by noise standards.
A beefier L99 was the end result of the modifications. The boosted 265 put out 339 hp at 5,750 rpm, with 364 lb-ft of torque at 3,250. This was an increase of nearly 140 hp and 125 lb-ft over the production version with only 8.5 psi. With another 5 pounds of boost, this little V-8 would have been at 425 plus horsepower, though the durability of the stock rotating assembly would likely have been diminished.
The performance was quite impressive and clearly indicative of the potential for a lot more. Coupled to a stock six-speed transmission and 3.42 gears, the Firebird ran 0-60 in 5.2 seconds, with a best of 13.47 at 106 mph in the quarter.
Though your author was not the one who piloted the Formula down the dragstrip, I did have a chance to drive the car quite hard in the summer of 1996. My impression was that the numbers didn't represent the actual performance this car was capable of at 8.5 pounds of boost. This engine revved very freely; the 3-inch stroke allowed the 265 to whiz up to six grand with enthusiastic ease. Overall, it felt like it should have been in the high 12s and there were more than 339 horses in there somewhere.
However, it didn't seem like the supercharged V-8's engine management programming had been sorted out completely. The engine had a tough time firing up and running from a cold start. When it did finally warm up, it was still running pig-rich. Soot on the rear bumper was excessive, and the throttle response was not nearly as tight as the black V-6 Trans Am, though being a prototype, one has to expect some problems.
Once the throttle was mashed, the soggy response was forgotten. After about 1,800-2,000 rpm, things happened very quickly. The 265 roared and felt like a much larger engine, and the torque output was very impressive and felt like it had an extra inch or so of stroke.
With the decade more of PCM tuning technology we have today, I often wonder how much easier it would have been for SVE to dial in the combination. Perhaps an afternoon in the capable hands of HPP contributors Chris White or Ray Bohacz would have wrung some more power out of the little 4.3.
Alas, it was not to be. Pontiac SVE was shut down years ago, and this particular Firebird, like the V-6 Trans Am, was crushed back in the summer of 2000. In the end, cubic inches were easier and less expensive to develop, so the big V-8 stayed in passenger car production as the threat of tightening regulations subsided.
In any event, this Firebird Formula and the Trans Am featured last month offer insight as to what was going on with Pontiac's performance car research and development. These little footnotes in Pontiac's history help us understand the Division's path in bringing certain cars to market, as well as some of the roads not taken.