National Firebird Club

If you're the typical motor head (like most of us), you're constantly wondering what small changes in your car would make in its performance. Would that higher-stall torque converter help? How about dropping to a lower gear? Until recently, the only way to tell was to actually make the change and measure the difference. Thanks to the high-tech world of computers, however, you can see how certain changes to your combination will affect performance without turning a wrench.

How does this happen, you ask? Through software programs like the Performance Estimator (Year One part # PE1). This piece of software, which runs on any 386 or greater IBM-compatible PC, allows you to enter a variety of information on your particular vehicle. The program then crunches the numbers and rewards you with "test results" based on your entries. The results include 0-60 mph time, quarter mile acceleration and speed, theoretical top speed, actual top speed, rpm in each gear, etc.

The entries you have to make include horsepower at the flywheel (net horsepower), shift points, maximum engine rpm, transmission and rear end gearing, frontal area and drag coefficient of your car (a table with most popular vintage and modern cars is included), weather conditions and traction coefficient. All this is explained in the documentation provided with the software, so it's not nearly as intimidating as it sounds.

The ability to print and save horsepower and torque curves for your engine is a nice feature of the software.

The most amazing thing about this software is how well it works. We tested it using information on a car that we've run at the drag strip several times. After entering the information, the Performance Estimator said the car should run a 13.55 in the quarter, and the car actually ran a 13.50. Since we already knew what the car ran at the strip, we varied the net horsepower entry until the software duplicated the e.t. and speed. This gave us the actual net horsepower the car was making. It's great fun.

At this point, we could enter changes in gearing, launch rpm, shift points, etc., to see what effect they had on the car's performance. Increasing the launch rpm, for example, slowed the car down due to a lack of traction. Dropping the rear gear ratio (higher numerically) resulted in reduced e.t.s until we exceeded the maximum rpm of the engine in third gear (the test car was an automatic). Just for fun, we gave the car 2,000 horsepower to see what it would do -- it broke! (Not really, it ran a lot faster.)

"Clunker" legislation is being proposed all across the country that could adversely affect our right to own vintage vehicles. We have produced an informative video that every enthusiast should see. The tape is $9.95 per copy and can be ordered by asking for part number CLUNKER.

Anyway, the Performance Estimator works very well as long as the information supplied to the software is realistic. Entering gross horsepower ratings resulted in very optimistic performance results, obviously, which proves what we've always heard about net horsepower ratings being much more realistic. That old computer axiom, "garbage in, garbage out", definitely applies, but when provided with something close to actual numbers this software is amazingly accurate. And the best thing about it? We made a bunch of drag strip passes and changed all kinds of equipment on the car, all from the comfort of our living room and without getting dirty. On to News & Reviews - Page 2

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