Jacobs Vehicle Systems has launched 1.5 Stroke HPD, a new variation of the company’s High Power Density (HPD) engine brake. The company says that this new HPD option provides heavy vehicles with significantly higher levels of supplemental braking force than traditional compression release braking, but with less complexity and cost than Two-Stroke HPD.

As with Two-Stroke HPD, 1.5 Stroke HPD provides small and medium displacement engines with large engine displacement retarding power. By adopting a different valve train and valve opening strategy than Two-Stroke HPD, 1.5 Stroke HPD has a more conservative technical strategy that will better suit the requirements of some engine hardware without compromising on performance.

“1.5 Stroke HPD is a new development resulting from Jacobs’ ongoing HPD prototyping programme. It follows the launch of Two-Stroke HPD, which was designed for a particularly complex engine design,” said Steve Ernest, vice president of engineering and business development at Jacobs Vehicle Systems. “It is a simpler and more affordable route that will see our customers achieve the same step-change in braking performance as with Two-Stroke HPD, if their engine hardware allows for that.”