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1975 Pontiac Firebird - Bottle-Stocker

Reality TV? The Reality Is They Don't Know Jack. We Take "Full Throttle" To School With Car Craft's

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Track Tested

First, we ran a couple of normally aspirated runs, which the TV show didn't do. Expectations weren't particularly high for a 160hp base motor that could easily run on moose juice, and a 15.67 and 88 mph proved that out. A backup run was 0.10 second slower so we punted and hit the squeeze.

The first attempt used a 100hp tune-up-and with a Depression-era compression ratio, we didn't bother to retard the timing. The Firebird responded with a 14.31 at 97.12 mph, an improvement of 1.36 seconds and 9 mph. We were already a solid 0.40 second quicker than the car had run on TV, and we were only getting started. It was obvious that Nick's vent fix had been worth the effort. Without a proper vent, the fuel pump will begin to lose pressure when it can't move the fuel out of the tank.

The backup run netted a slightly quicker 14.28. That's when Nick decided to go for all the glory and pill the Pontiac with the 200hp shot. Nick swapped the jets, pulled the timing back 4 degrees, then stood on it. The results were less than spectacular, delivering only a 14.21 at 98 mph. We decided to swap in our fresh Nitrous Express bottle to pump the pressure back up to 900 psi. After two runs, Nick had managed a 14.05, then-frustratingly close to the 13s-a 14.01.

The 60-foot times were still slow at 2 seconds flat even though Nick was hitting the squeeze right on the starting line. Worse, we could hear the engine wavering in high gear all the way through the lights. By now we'd improved by almost 0.70 second with some simple tune-up tricks, so we figured we had reached the Firebird's power limit.

Keep in mind we were trying to add 200 hp worth of nitrous to an engine originally rated at 160 hp. Granted, we had a better induction system, but the Edelbrock carb and intake were probably not worth 25 hp, which would only make this a 185hp engine. Trying to add 110 percent worth of power is asking a lot.

We packed up and started back home. About five miles later, the Firebird ran out of gas even though the gauge still read a quarter tank. After some ribbing and a call to Lauri to come bail us out, we realized we could have gone quicker at the track-the Firebird was probably laying down at the top end because it was sucking more air than fuel from the tank.

Even with our blunder, we improved the TV car's performance by about 7 car lengths and all we really did was change the spark plugs, vent the tank, and change the timing curve. Sometimes it's not the parts you buy, it's maximizing what you have.

E.T. @ MPH E.T. @ MPH
Observed Corrected Description
14.80 @ 95 - First TV pass at Fontana, 100hp tune
14.70 @ 94 - Second TV pass at Fontana, 200hp tune
15.67 @ 88.77 15.16 @ 91.76 First baseline pass, no nitrous
15.87 @ 87.80 15.36 @ 90.75 Second baseline pass, no nitrous
14.31 @ 97.12 13.85 @ 100.39 100hp nitrous tune
14.28 @ 96.97 13.82 @ 100.23 Same as above
14.21 @ 98.34 13.75 @ 101.65 200hp nitrous tune
14.05 @ 97.09 13.59 @ 100.36 Fresh bottle, same tune
14.01 @ 97.82 13.55 @ 100.36 Same as above
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