Hemispherical combustion chambers were introduced on some of the earliest automotive engines, shortly after the viability of the internal combustion engine was first … See more

Although a wedge-head design offers simplified valve actuation, it usually does so by placing the valves side by side within the chamber, with parallel stem axes. This can … See more

Alfa Romeo
Alfa Romeo has produced successful hemi-head engines throughout the years. Arguably one of their … See more

A hemispherical head ("hemi-head") gives an efficient combustion chamber with minimal heat loss to the head, and allows for two large valves. However, a hemi-head usually allows no more than two valves per cylinder due to the difficulty in arranging the valve … See more

In the modern emissions-era, the hemi-chamber has morphed into more sophisticated and complex designs that are able to extract more power with lower emissions from any … See more