Stock Car Technology - Data Acquisition

Because the basic system samples only two sources, even an outdated computer has enough processor horsepower to do the job. "A lot of folks buy the system and dedicate the computer in the closet-the one they were going to throw out-to the race program," Scaler says.

As a team gets more involved and the needs more sophisticated, they can add data on things such as throttle position, brake pressure, and g-loads. "With g-loads we can map the track and overlap laps and really find out where a driver is fast from lap to lap," Scaler says.

Here are some tips on cameras and timers: Mount the camera as high as possible and as near to the driver's line of vision as is practical. While you can make your own mount, commercial ones are about $100 and are much easier to use and adjust. No matter how you mount the camera, add a tether strap to it so, in case of a crash, it doesn't become something else being tossed around inside the car. Also, if you use both a camera and a timer, be sure to switch off the infrared receiver on the camera. If you don't, the timing beacon can switch the camera off (and sometimes on again) when the car passes through the beam.

For the past decade, Steve Hodge was among the most serious contenders in sports car racing on the West Coast. He campaigned a Camaro in the Trans Am series and won the Sports Car Club of America's Rose Cup (among the club's most significant races) an unprecedented four times in a row. Then he decided to go circle track racing.

"It was a pretty steep learning curve," says Hodge, an engineer for Warn Industries, who helps sponsor his Monte Carlo. "We found out there was a lot we didn't know."

Some of what they did know-data acquisition-helped them flatten the learning curve. When Hodge, his father, and brother built their new car, they transferred the SPA data logging system from the road course to the circle track machine.

On Hodge's Chevrolet, the SPA system records suspension movements, g-loads, engine speed and throttle position. The data is transferred to a laptop computer where it gives a visual record, or trace, of everything the car did on every lap.

"For a guy just beginning, the biggest advantage with the data acquisition is being able to compare what a new driver does to someone who really knows how to hustle a car around an oval," Hodge says. "I could go out and run laps and then put someone with a lot of experience in the car and lay my trace right on top of his to see where they are different."

Among the things Hodge learned is that many oval-track cars are set up with the wrong gearing.

"Drivers want to have lots of power coming off the corners, but by looking at the throttle position and engine speeds, we figured a lot of guys are on the downside of the torque curve at the end of the straights," he says.

He was also surprised at the amount of wheel movement. "We think that right-front corner just takes a set and is fully loaded going around a corner, but it is really moving up and down a lot," he says.

Hodge also says the system help him overcome every driver's tendency to compensate for the car. "I'd find myself playing with the throttle through the corners to help get the car to take a set and turn in, but what I was really doing was driving around a handling situation we needed to overcome," he says.

The system Hodge uses retails for around $2,000. Just a few years ago it would have been nearly five times that much. Hodge says if a driver asks around, it is possible to rent equipment for pre-season testing.