From the 1920s to the 1970s, the evolution of engines (measured by compression ratio) and the evolution of fuels (measured by octane rating) occurred in tandem. Gasoline octane improvement during that ...

As you may know, an engine's compression ratio is directly linked to its combustion efficiency. All else being equal, higher-compression engines tend to make more power while offering better fuel ...

Everything you need to know about the numbers on the gas pump.

Harry Ricardo built the first known variable compression ratio engine as a test engine in the 1920s to study knock in aircraft engines. Variable compression ratio was achieved by raising or lowering ...

“Compression ratio” is a term thrown around a lot when you’re talking about engine specs, but what does it really mean? For the most part, when people are talking about an engine’s compression ratio, ...

Using regular gas to power your EcoBoost engine is possible, and it'll cost you less at the pump, but you may want to use a ...

Tucker Ryals;Gainesville, FL: I'd like to pose a question regarding an article Jeff Smith wrote on the Chevy 5.3L motor "Bolt On a Cam and Heads and Add 120+ HP" (April '08). I read the article with ...

Today's low-octane unleaded gas mandates a compression ratio reduction for '60s supercars. The easiest way to lower compression is usually to swap on late-model heads; not only do their larger ...

The fact that you're reading this now means there's a pretty damn good chance you pump gas into your car. And because of that, you've got a combustion engine under your car's hood. Of course, some of ...

Compression: An automotive term used by everybody, forever. Let's get into some detail and maybe develop a better understanding. Pressure, and more pressure: It's a must-have to produce power within ...

Labeling different gases as “regular” and “premium” is a bit misleading, as many cars only require regular gas and should only run on regular gas. Premium gasoline is not necessarily a luxury product ...