The compression ratio isn’t just a number: it’s one of the greatest determining factors in engine building. Compression ratio determines the type of fuel, how much boost, and has a significant ...

Cylinder head milling has long been known as one of the shortest and easiest routes to increased performance. A few thousandths of an inch carefully machined from the surface of the head will increase ...

Strictly defined, compression ratio is the total volume above the piston at bottom dead center (BDC), divided by the total volume above the piston at top dead center (TDC). First, let's look at the ...

Pretty simple question actually (or so my ignorant mind thinks): At what compression ratio would an engine benefit from higher octane fuel? The Focus I drive is just over 10:1, and I've heard some say ...

Diesel engines are different from gas engines in numerous ways, including their use of high compression ratios. Here's why that is and what it means.

A gasoline piston engine that can dynamically change its compression ratio —that is, the amount by which the piston squeezes the fuel-air mixture in the cylinder—has long been a holy grail of engine ...

Mazda’s new SkyActiv-X engine will go against every convention you thought you understood about gasoline engines. It’s supercharged, but for efficiency purposes, not to increase power. It has a ...