Assuming a properly tuned engine, there are three factors that contribute to poor streetability: long cam duration, high compression ratios, and excessive cruise rpm. Since cam selection is largely ...

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 ...

You've heard the term compression ratio before, but have you ever wondered exactly what it means? Well, it's time to explain exactly what compression ratio is, and why every carmaker is now obsessed ...

Increasing an engine’s compression ratio is a proven way of unlocking extra horsepower, but there’s a point of diminishing returns. The team at Garage 54, the Russian mechanics who built a V16 using ...

The theory is simple: Improve efficiency by adjusting the effective size of the engine to produce the power needed at any given moment. In practice, the hardware to do it is more complicated. Only a ...

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 ...

Forget variable length intakes and variable valve timing, Infiniti is going all the way and introducing variable cylinder compression ratios. The new VC-T turbo engine automatically adjusts between a ...

The Porsche-Hilite technology is comparatively simple, and could be offered to every automaker if and when VCR comes to market. Share on Facebook (opens in a new window) Share on X (opens in a new ...

ABSTRACT An experimental investigation has been carried out to compare the indicated performance and heat release characteristics of a DI diesel engine at compression ratios of 18.4:1 and 15.4:1. The ...