What is a Rev-Counter?

It usually takes a boy racer to see if a car gets to the redline for each of the cars gear-shifts. And, it usually takes an old and experienced hand to do it smoothly, and in a quicker time.

Second to the speedometer is the rev-counter (or more appropriately termed tachometer), which has kept many a little boy mesmerized with its flicking hand skipping up and down through the engines entire rev range.

Many people have slipped into using the term rev-counter (short for Revolution Counter) in place of the correct application of the term tachometer. The term tachometer comes from Greek ?????, tachos, “speed”, and metron, “to measure”. The revcounter/tachometer display on automobiles and other vehicles shows the rate of rotation of the engine’s crankshaft, and typically has markings indicating a safe range of rotation speeds.

Hop into the driver’s seat of most cars these days and you will find sitting inside the dash as part of the instrument panel the tachometer/rev-counter display. The tachometer displays the full force of the engine’s twist under the bonnet, as it shows the rotation of the engine’s crankshaft in rpm (Revolutions Per Minute)-at a given moment.

Some sports car engines these days are starting to compete with the two-strokes of old that screamed and whined into the night as the engine was held under full throttle.

The main use for a rev counter is not just for looks, but of course it tells us when it’s time to change gear. If the needle approaches the red section, then it’s probably time to consider changing up a gear or you run the risk of doing some major damage to the engine. Modern vehicles come with a rev limiter attached which prevents the engine’s crankshaft from rotating beyond a safe operative level.

We hope that helps answer the question ‘What is What is a Rev-Counter?’!

Back to Car Glossary