T-head engine

Detonation, a leading cause of catastrophic engine failure, necessitated managing both the temperature and compression of the highly volatile gasoline vapor for maximum reliability.

The relative inefficiency of the T-head engine was offset by significant reliability gains and suited the lower travel and racing speeds of the era.

However, as other engine designs enhanced their reliability during World War I, the T-head's performance limitations led to its decline in racing applications.

The T-head engine became obsolete in passenger cars due to advancements made during World War I and the introduction of anti-knock compounds like tetraethyl lead in the early 1920s.

The Pierce-Arrow company introduced a production four-valve per cylinder T-head motor (Dual Valve Six) in 1918, one of the few, perhaps the only, multi-valve valve-in-block type engines produced.