Ad Radar
Car Craft
Click here to find out more!

1991 Pontiac Firebird Formula - Build A 12-Second TPI Pontiac Firebird

It Has No Clever Name, But It Sure Is Slow.Enjoy The Victories And Defeats As We Show You How To

Photography by ,

'In the last few issues, we've been toying with a '91 Firebird Formula trying to get its wheezy 5.7 to produce enough power for a decent timeslip using only bolt-on parts. It has over 150,000 miles on the odometer and a stock engine. It is option-loaded from the factory, so it weighed 3,778 pounds full of gas with driver on race day, and we ran it through full exhaust with a cat. That being known, on the last pass just minutes before the track closed we clicked a corrected 12.70 at 105 mph. The next day we had a huge argument about using the NHRA correction factor for nitrous runs. Freiburger says not to use it. Glad says all times must be corrected to keep things consistent. Smith says that there is a special nitrous-car correction factor that he saw once. And the NHRA does not correct nitrous cars. What do you think? Tell us at

Regardless, we used simple intake and exhaust mods, a couple of starting-line leverage tricks, and a nitrous plate from Nitrous Works. The beauty of this car is that it's nice and legal. We haven't touched the cam or the short-block, so we can drive it every day, then sneak-attack dudes with a holeshot and a 105-mph trap speed. It's as close to an all-around street/strip car as you're gonna see.

But the price! If you're choking on your Monster Thick Burger at the sight of the price list, remember the thing broke down to the tune of about $1,000 in parts on day one and we've included the price of the car itself. So this is the out-the-door, driving it daily, ripping 12s in front of a crowd, no tuning knowledge required, and making it to work on Monday price. Does $7K still hurt?

And there's a lot more room to go faster. The choices are: Do we crack open the engine and work the heads and cam and risk rendering it illegal or possibly cranky in the morning? Or do we add increasing amounts of nitrous oxide with the fuel- and ignition-system upgrades to handle the task? Originally we had intended it to be a nitrous car for cheap and easy speed, but at this point we can go a lot further either way.

So do you love it? No one seems to want to name this thing, but that doesn't mean we can't beat it some more. For now we are going to commute in it and take it to the track on the weekends. We'll let you know if it breaks in the Behind the Scenes section. Just look at it like a Motor Trend long-term road test for guys who get it.

Yesterday's RunTo catch you up, we picked up a stock '91 Formula for $1,500 and proceeded to fix a ton of failing parts to the tune of $2,024.72 then added a cool set of SLP headers, a cold-air intake, and some intake runners. We also tuned up the exhaust with a performance 3-inch cat from Random Technologies and an after-cat also from SLP. We ended up with a corrected 14.19 at 95.94 with a 60-foot time that ranged around 2.20 seconds with the best time of 2.15. About 0.20 slower than our '91 Z28 we ran back in 1999, but that car was lighter than the Formula and had a very loud muffler cutout.

Enjoyed this Post? Subscribe to our RSS Feed, or use your favorite social media to recommend us to friends and colleagues!
Car Craft