Dear Tom and Ray:

Does putting bigger wheels on your car make the speedometer read faster or slower? I've got a bet on this. Jim

Ray: The speedometer will read slower, Jim. The speedometer reading is based on how many times the axle turns. With bigger wheels, the axle will turn fewer times to cover the same distance, so the speedometer will think the car is going slower.

Tom: If you don't believe us, put on some larger wheels, bring your car up to the "speed limit" on your speedometer, and drive through your favorite local radar trap (preferably with a smile and a wave). I'm sure the nice police officer will be happy to confirm that you were, indeed, going faster than your speedometer led you to believe. In fact, you'll even get a written confirmation of this should you need it to settle the bet.

Everybody wants a new car. But from a purely financial point of view, there is no question that buying a used car is always cheaper, even in the long run. To learn more, order Tom and Ray's pamphlet How to Buy a Used Car: Things That Detroit and Tokyo Don't Want You to Know. To order, send (check or money order) to Ruin, P.O. Box 536475, Orlando, FL 32853-6475. You can also order online.

© 1995 by Tom and Ray Magliozzi and Doug Berman Distributed by King Features Syndicate, Inc.

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