The early 1969 and 1970 heads had larger valves and ports for better performance.

The heads are off, so you can see the large valve and rocker mechanisms.

This engine used larger valves and carburetors than previous years.

This essentially is a long collection of very large valves that can be closed against storm surges.

Bolted bonnet is used for larger valves and higher pressure applications.

The engine's large bore allowed for larger valves to be fitted.

An increase in bore to 120 mm allowed space for these larger valves.

The original Chrysler design of two large valves per cylinder is used.

Atop the machine, Barnaby saw a large valve near his hand.

Multiple valves arranged to be triggered together are occasionally used as an alternative to a single larger valve.