The phrase "hydraulic roller" refers to a type of mechanism in an engine. It uses hydraulic pressure to control the movement of a part called a roller, which helps the engine run smoothly and improves performance. Full definition
Dynamic Response improves vehicle handling through hydraulic roll control, optimizing on - road performance and passenger comfort. (landroverusa.com)
It has a fuel - injected 408ci engine based on a 6.0 - liter truck block, Lunati steel 4» crank, ported LS6 heads, 2.8 - liter Kenne Bell supercharger, COMP Cams hydraulic roller camshaft and a Tremec T56 6 - speed manual transmission. (barrett-jackson.com)