See also:

Tachometer
The tachometer indicates engine speed in revolutions per minute (rpm). Do not rev engine into the red zone 1 . CAUTION When engine speed approaches the red zone, shift to a higher gear or reduc ...

SENSE AND STYLE
Family Friendly (Not Really, Fair, Great, Excellent): Fair Fun-Factor (None, Some, Good Times, Groove-On): Good Times ...

Octane rating tips
Using unleaded gasoline with an octane rating lower than recommended can cause persistent, heavy “spark knock.” (“Spark knock” is a metallic rapping noise.) If severe, this can lead to ...