Variables Of Mustang Drag Racing by Brenspeed

The Variables of Racing

We took the time to write this article to inform you about the variables of racing. Most performance enthusiasts do not understand that variables can make a drastic difference in quarter mile ET’s from one vehicle to another. They also do not understand that racing their mustang one weekend then visiting the drag strip again a week or even month later can also present a large amount of variables. We have put multiple drivers behind the wheel of the same car and quarter mile times have varied up to 2 seconds. We have also taken two cars both with the same modifications and also seen a big difference in ET. With that in mind we would like to explain “The Variables Of Racing”.

The Vehicle:
We see almost on a daily basis 100% stock Mustangs have a pretty large horsepower variance. We refer to these mustangs as high producers and low producers. We have seen over a 25 horsepower variance back to back on the same day with completely stock vehicles. This alone can be a big variance when trying to compare your mustang to another mustang at the drag strip.

Another great thing to look at is the vehicle weight. Once you calculate in wheel and tire options, vehicle options, and the drivers weight you can see a 400+ pound variance in vehicles. It has always been safe to say that 100 pounds of vehicle weight will usually cost you about a tenth in the quarter mile. So take that 400 pound weight difference and you now have a car that is 4 tenths slower than the lighter one. Also take into account a gallon of gas weighs about 6 pounds you now just added over 70 pounds to the car running a full tank vs. leaving a few gallons in for racing.

The Driver:
All of the weight and horsepower figures listed above truly add up to a lot of performance but the driver can be a huge and often the largest variable. To test this theory we have let a variety of drivers test various Mustangs on the same day at the same track and found a huge difference in ET. Launch style, shift points, tire spin, bogging, and time between shifts all play a role into seeing ET variances anywhere from a half second to even 2 seconds on higher horsepower supercharged vehicles. Not very often do two non professional drivers handle the vehicle exactly alike.

The Track:
We have found that no two drag strips always produce the exact same ET’s. We have also found that visiting the same dragstrip even on a weekly basis will not always produce the same ET. Some of the variables that play a role in variances from one day to the next are your environment like elevation, temperature and humidity. Also engine temperature, air intake temperature, engine heat soak, traction, and the tracks timing system all play a role in elapsed time. All those variable just listed can cause several tenths in variance and when you get into high elevation you are affected even more.



The Modifications:
The performance modifications and octane fuel are the easiest variances to document and unfortunately they are usually the only variances a person uses as a comparison. To only use a few parts that may increase the cars performance a half second as your comparison yet ignore variables that can slow it down over a second is completely inaccurate. If you have two cars with the exact same modifications and you are not running the exact same ET read the paragraphs above. It is completely common to see two vehicles not running the same ET. When taken into consideration there are enough variables in this article to produce a huge difference in performance and that is typically when two vehicles do not run the exact same ET.