CART: The Electronic Senses of a Champ Car

4 September 1998

The Final Installment of a Four-Part Series Relating Racing Electronics to the Human Body

PLYMOUTH, Mich. (Sept. 2, 1998) -- As human beings, we rely on five critical senses to monitor our surroundings: our sense of smell, hearing, touch, sight and taste gather important information.

Champ cars rely on senses as well. They have approximately 45 electronic sensors which monitor their environment. On the eight Mercedes-Benz powered Champ cars utilizing the IC108E engine, these sensors are located throughout the engine, transmission and chassis.

These sensors provide information to the Magneti Marelli electronics and fuel management system, which was developed specifically for the IC108E. They can monitor movement, temperature, pressure, and even determine the chemical properties in the intake and exhaust gases.

"When you read your fuel or temperature gauge on the dash of your personal car, you are reading information gathered by a sensor," said Giancarlo De Angelis, manager of Magneti Marellis motor sports program. "The sensors on a street car let the driver know the car is working properly. It is the same on a race car. Our sensors collect information that is crucial for the engine management system to operate properly.

"The most important sensors are located inside the engine to tell us exactly what is happening at all times. This information is fed to the Magneti Marelli engine control unit and data logger, as well as to the engineers in the pits for monitoring.

"There are sensors for engine temperature, various pressures, fuel consumption, speed, rpm and many other parameters," continued De Angelis. "All of this information tells us exactly what is happening with the engine at all times."

Depending on the application, one sensor can range in price from just a few dollars up to $2,000. Considering the value of the data these sensors supply, it is not a high price to payespecially when you consider the value of the engines and race cars they help protect. Race-ready Champ cars each cost in the neighborhood of $1 million.

What is most remarkable is the sensors work despite being exposed to extreme heat and vibration, as well as to fuel, oil and water. "Our engineers spend several hours a day, sometimes seven days a week, analyzing the data these sensors provide," said Paul Ray, vice president of Ilmor Engineering, the race-engine design and manufacturing arm of Mercedes-Benz. "We use this information to improve the performance of the car, prevent problems on the track and to keep the driver safe. If we see a problem, we can bring the car in before it gets to the point where it could be a safety hazard."

Various sensor types which feed information to the Magneti Marelli Engine and Fuel Management System on the Mercedes-Benz IC108E:

 Temperature
 Pressure (oil, fuel, water)
 Acceleration
 Braking
 G-force (gravity)
 Steering Angle
 Suspension (shocks)
 Load Cell (on suspension, measures the weight on the wheels)
 Pitot Tube (measures air speed)

Based in Milan, Magneti Marelli is an international supplier of automotive components and systems, including: engine control systems, instrument panels, air conditioning systems, lighting, fuel delivery systems, mirrors, exhaust systems, mechanical and electronic components, shock absorbers and lubricants. In addition to Mercedes-Benz, Marellis clients include Chrysler, Ferrari, Fiat, Ford, General Motors and Harley-Davidson, contributing to combined worldwide sales of more than $3.9 billion.