Jacobs, Tula to Accelerate Cylinder Deactivation, Dynamic Skip Fire Development
Jacobs Vehicle Systems and Tula Technology have signed an agreement to accelerate the development of Jacobs cylinder deactivation valve actuation technology in conjunction with Tula’s dynamic skip fire control algorithms.

The agreement will allow technical development to expand the operating range at which emissions reductions can be achieved when CDA and DSF technology is combined.
Photo: Jacobs Vehicle Systems
Jacobs Vehicle Systems and Tula Technology have signed an agreement to accelerate the development of Jacobs cylinder deactivation (CDA) valve actuation technology in conjunction with Tula’s dynamic skip fire (DSF) control algorithms.
The agreement builds on two years of research and development collaboration between the two companies to reduce nitrous oxide and carbon dioxide emissions from medium- and heavy-duty vehicles.
Independent laboratory testing has demonstrated that Jacobs CDA hardware and Tula’s diesel DSF achieve greater emission reductions when combined, Jacobs officials said in a press release.
Low-load cycle performance was estimated with a well-calibrated powertrain simulation tool to accurately capture the low-load system operation and emissions. This system showed as much as a 5% decrease in CO2 and a 74% reduction in NOX emissions compared to the baseline technology, company officials said.
“While CDA and dDSF are available to commercial powertrain manufacturers as separate systems, our experience indicates that integrating the two technologies delivers much greater benefit to today’s medium- and heavy-duty engines,” said Steve Ernest, vice president of engineering and business development at Jacobs Vehicle Systems. “We have been working with Tula for several years, and this formal agreement solidifies our relationship as we demonstrate the benefits of using CDA and dDSF in tandem. Our efforts will provide the marketplace with sought-after solutions to meet increasingly challenging emissions standards. The synergies created through multiple development projects will offer customers the best possible outcomes for reducing NOX and CO2 simultaneously.”
The agreement will allow technical development to expand the operating range at which emissions reductions can be achieved when the two technologies are combined. Jacobs and Tula also will explore opportunities for reduced NOX and CO2 emissions in off-road vehicles and equip a Class 8 demonstrator truck with both Jacobs’ CDA and Tula’s dDSF technologies for customers to experience firsthand.
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