There are many books and webpages that suggest ways of increasing the speed of a Pinewood Derby. But, how do you know which techniques really work or when your continuing efforts have become unproductive? For example, nearly everyone knows that polishing the axels can improve your car's speed, but how can you determine if additional polishing will be beneficial? After a little thought, the answer should be obvious. You can't really evaluate the effectiveness of your modifications unless you can measure your car's speed throughout the alteration process. This book shows you how to construct a low-cost, PC-based timer so you can truly maximize your car's performance. You won't just learn what to do, though. You will also learn enough about electricity and programming to truly understand how everything works in case you want to improve or expand upon the timer itself.