Ed K

I’ve been involved in Beta testing a new automobile performance simulation program and am interested in your comments. It is the creation of a young engineer/auto enthusiast and is based on the physics behind a car’s performance. It allows you to input the specifications of a car (I used the data in the Acura brochure) and get all the test results immediately. These include dyno graphs, gearing vs. speed plots, acceleration times for various distances, and top speed. Once you setup a car it can be saved for future use. One feature of the program is that you can then try various modifications regarding engine, transmission, weight, tires etc. and compare the results. The program goes beyond just showing numbers and plots. It has a realistic drag race between any two cars that you select. The race display is very complete with the standard light tree, sound effects , tachometer and speedometer for each car. The drag distance is also selectable from 1/8th mile on up to 5 miles. You can elect to have the program give an optimum start and shift points, select the shift points yourself, or manually control the start and shift points of either or both cars in real time. This last mode allows you to use the program as a game, testing your skills against the computer or another player. It even “red lights” if you leave early. If you shift too late there is a rev limiter that affects your time. The computer controlled modes are useful in performance enhancement comparisons so that the user effects are eliminated.

I found that inputting the specs for my TL-S and adjusting the traction setting slightly I could match all the road tests in the magazines. I also found that the top speed is highest in 4th gear. I then got some of the dyno data from Snook’s site and saw what the performance increases looked like at the track. I played with rim sizes, tire sizes and types. I even changed the transmission to a 6 speed close ratio. In every case the results were believable and the changes were very easy to input and save.

Using the “engine shop” part of the program I tried the effect of lowering the compression ratio and supercharging, turbocharging, nitrous oxide and various combinations. The boost can be set by the user and again the results were believable. I don’t know if the engine I created would blow up when I reached 527 HP but it sure was fast.

The program can even simulate a top fuel dragster, which has only one gear and gets some gear change effect from the centrifugal tire diameter change as it goes faster.

The program has a library of many cars ranging from the VW bus and Yugo to Porsche’s, Ferrarri’s and top fuel dragsters. You can add as many of your own cars as you like.

This program would be useful in estimating performance add-ons before buying. It would also allow you to test shifting strategies before racing. It only deals with straight line performance and would not be useful to evaluate handling improvements. The program should be released this Fall. It is called PC Hotrod and the company is Lightspeed Performance Software, Inc. I’ll post more info when it is available.

MafiosoTL

that sorta software is already available, my friend has it on his computer, he's had it for over acouple years now.

bigman

can any of you give me a url so that i could look into this type of software. I would like to look into it. I knew it existed but not comercially.

Ed K

Since my only involvement with this program was to check the mathematics, physics and test the program for bugs I emailed the author, W. J. Mercer for comments. He was aware of other programs that attempted to do the same thing but found them lacking. Since he was trying to evaluate possible modifications for his own cars he wrote the first version of this program. He then refined it for release as a product. The program works in the Windows environment and is very user friendly and has complete Help files. He expects to sell the program for less than $50. The following are some excerpts of his reply:

“The programs that I have seen so far that do sort of what my program does are asfollows:

The Car Performance Calculator). This program is something like $300 and is quite a bit more detailed than my program (but is all this detail useful?). It has no drag race screen and the graphs are not as neat and large as my program.

Desktop Dragstrip). This program is $50, but I have been disappointed in it's lack of accuracy and difficulty of data entry. For instance, one must know the car's frontal area in sq. ft. and their are no estimator's. Also, one must somehow know the tires height... it has no entry for radial sizing. Also when I put the crank hp of my Miata in stock form in the program it was way, way too fast (14.9 ET yeah right). I finally figured out that this program needed rwhp to be accurate. It must assume 100% drivetrain efficiency. The data entry is also more archaic than my program (DOS like, even though it has a windows interface) and it has no drag race screen either. I am not impressed with its printouts either.

I have also run across an old DOS program that I forget the name of. It was programmed down in Louisiana somewhere. It asks a bunch of disjointed questions like whether the engine is 1)cold 2) warm 3) hot or 4) burning, whether the camshaft is 1)stock 2)performance 3)hot street 4)wild LOL. Needless to say, I am not impressed with that program. In fact, it is the exact kind of archaic automotive thinking that I am trying to debunk.”

“Along with the better modeling and ease of data entry, I think one of the biggest strengths of my program is that you have many functions built into one program. You can build any piston or rotary engine, try any tire you wish, and very importantly have a realistic and fun real-time drag race, in addition to the basic car performance estimation. The drag race adds a visual impact to your mods that also aids you in understanding exactly how mods are effecting the performance and also better see where you might need to upgrade. It is pretty neat how you can change just one thing on a car, such as changing to a lightened flywheel, and watch how this one change effects the car as it accelerates. In this example, you can see how the car gets the biggest boost in the lower gears. Sometimes the impact of, say, an 11.6 ET vs. an 11.9 isn't really realized with just the numbers, but when you watch the cars racing on the drag strip, it really becomes apparent. Of course, the reason this all works is that I am using the same car model throughout all areas of the program. In fact, having these different ways of viewing the car's performance is the way I have cross-checked the realism of the car model.”

“We are going to try to get our website up and running as soon as possible. Perhaps we will at least get some screenshots of the program up first. Then eventually have a link for buying the product.”