Car Talk

February 1994

Dear Tom and Ray:

Husbands can be so excitable. When I told mine that the tachometer reads 2,000 rpm while I'm in second gear, he was not his normal, calm self. I'm trying to find out what the tachometer is there for, and what it means to me while I'm driving and shifting. Should I even pay attention to it? Please tell me all I ever wanted to know about tachometers, in 150 words or less, without the exasperation and frustration my husband exhibits. [redtruck.gif] Sandy

Tom: 150 words or less!! Are you crazy, Sandy?? Who do you think we are, Ernest and Julio Hemingway???

Ray: Husbands ARE excitable, aren't they, Sandy? Here's everything you need to know about tachometers in less than 150 words:

Tom: Tachometers tell you how fast the engine is spinning in "revolutions per minute." And the only reason you care is that you don't want the speed of the engine to be too high or too low.

Ray: Fortunately, you don't really need the tachometer to tell you that. When the engine speed is too low, the car will buck and chatter and ping on acceleration, and may even stall. That's your cue to shift to a lower gear.

Tom: When the engine speed is too high, you'll hear the engine screaming, and eventually, one of the pistons will come flying up through the hood. That's your cue to shift up to Second, or get out of the passing lane.

Ray: So, if you can drive by just being aware of the sound and feel of the engine, why do so many cars have tachometers these days?

Tom: Well, there are some people who like to know exactly what their engine speed is. Just like there are some people who like to know exactly how many volts their alternator is putting out.

Ray: But in most cars, the real reason...the basis of the existence of this tachometer... unknown to most people... is that it's there to replace the clock.

Tom: Right. If you're over 40, you may remember that there used to be a big, round clock on the instrument panel, next to the speedometer. But now that almost all cars have digital clocks, there's a big round space they need to fill. And it was either a tachometer or a color photo of Dan Quayle in a tutu, and the tachometer won by a nose.

Ray: How many words was that?

Tom: 270.

Ray: Tough. And by the way, Sandy, tell your husband he can relax. 2,000 rpm in Second gear--or any gear--is just fine.

Tom and Ray share secrets mechanics don't want you to know in their pamphlet Ten Ways You May Be Ruining Your Car Without Even Knowing It! To order, send (check or money order) to Ruin, P.O. Box 536475, Orlando, FL 32853-6475. You can also order online.

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