Liters, defined.

Dear Car Talk

Dear Car Talk | Mar 01, 1993

Dear Tom and Ray:

I am confused about the meaning of the term "liters." What does it mean? Is a high liter rating better than a low one? My car says 2.0 liters.

RAY: Well, there are several types of liters, Frank. There's the kind that the little green men refer to when they get out of their spaceships. You know, "take me to your liter."

TOM: A liter is a metric measure of volume, Frank. It's a little smaller than a quart. If you go to your supermarket, and head over to the soda aisle. you'll see that those real big bottles of Coke are 2.0 liters. The same size as your engine!

RAY: Actually, the engine itself isn't that size. 2.0 liters is a measure of the engine's displacement--that is, the total amount of space in all of the empty cylinders. So if you took out all four spark plugs, and one by one, set each piston at the bottom, and filled the cylinders with Coke, you'd have just enough Coke in that 2 liter bottle to fill them all up. And who knows, you might make the car run better, too.

TOM: What the displacement tells you, Frank, is approximately how much power the engine can produce.

RAY: It's not an exact measure, because some 1.8 liter engines actually produce more power that some 2.0 liter engines, because of other mechanical differences. But generally speaking, a 3.0 liter engine is going to be more powerful than a 2.0 liter engine, because it can burn more air and gasoline for each revolution of the engine.

TOM: And which is better? That really depends on the car. A big, heavy Lincoln Town Car with a 2.0 liter engine would be a complete dog. But a Saturn with its 1.9 liter engine has plenty of power. It's kind of like a hat, Frank. You don't necessarily want the biggest one, you want the one that fits.

RAY: Except in my brother's case. Then you want the one that covers as much of his face as possible.

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