Greetings! I have never built an electronics project like this, however, I do understand the basics of what needs to be done. We are building a car that will run on the Bonneville Salt Flats in 2010. What I am looking for is to build a device to show the difference in wheel speed between the front wheels and the drive wheels. The reasons for this is to give the pilot information on how much traction he is getting at the rear wheels. Since the engine and drive wheels are located 15 feet behind the driver, you cannot do this by ear (especially at 400+mph). The second reason is that the tires used at these speeds cost $800 each, there will be 4 drive wheels, that's $3200 worth of tires. Because of the speed, the tire treads are very, VERY thin, any spinning will destroy the tires in short order. It's not just a money thing, at 400+ getting a flat tire could be fatal. My current thought is to place wheel speed sensors at one front wheel and one drive wheel. That data will be collected and one value subtracted from the other. That difference will be presented to the pilot. I am not opposed to an LCD display or a series of lights that will indicate 5, 10,15, 20 and over 25mph difference. I am a computer programmer by trade and we are planning to integrate a PC into the car for data logging and tuning. I will have a complete CPU available managing the input and output. If we can use the PC to create an application to do this, it should not be an issue. If it is easier/better to build a chip-set to do this, we can go that route as well. I am open to any and all ideas, I have a rough idea of what needs to be done, just no knowledge of parts or processes to complete it. Thanks, Brandon.