Schaeffler: Run On Two Cylinders Instead of Three

Cameron Aubernon
by Cameron Aubernon

Cylinder deactivation is available on a handful of Chrysler and General Motors V8s, as well as Honda V6s, cutting power to a set of cylinders in order to boost efficiency in the short-term. However, one supplier wants to take this further by using the technology on turbocharged three-cylinder motors, deactivating one cylinder while the other two do all of the work.

Ward’s Auto reports German supplier Schaeffler, which brought the switchable valve lifters to the Chrysler and GM cylinder-deactivation programs, is looking to help its customers develop three all-new three-cylinder engines that will put aside one cylinder under certain conditions. Manager of valvetrain systems David Kehr hopes the first prototype will be available for driving in six months, and believes the tech is ready for small engines thanks to advances in NVH:

It will make sense when the consumers don’t even know it’s there. To tell someone you’re going to do it, they’d probably have a lot of apprehension. But even with all the cylinder-deactivation applications that have hit the market, I would argue most people don’t even know it’s there.

The supplier plans to use electronic “rolling” cylinder deactivation, changing the amount of cylinders in play — and which ones — based on driver behavior. In turn, this would boost fuel economy over the long-term, even though it would also add cost to the engines that receive the tech. Thus, the focus will be on three-cylinder units as the cost of adding cylinder deactivation is much lower than even on a four-cylinder unit, let alone using ICEs with electric power in a hybrid configuration to do the same thing.

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  • Jacob_coulter Jacob_coulter on Jul 11, 2014

    As GM owners how their cylinder deactivation is working out for them on the LS V8's, it's caused all sorts issues resulting in complete engine rebuilds or replacements. All to meet some ridiculous CAFE quote and "save" the consumer a few dollars a month in gas, never mind the thousands in repair bills. Oil starvation is the main issue. Buy hey, they got 19mpg on the highway instead of 18.2 mpg, so it was totally worth it. Many people buy kits that disable this feature through the ECM because they don't want to have to buy a new engine at 60k miles. It also causes all sorts of bad oil consumption issues.

    • See 3 previous
    • Blowfish Blowfish on Jul 14, 2014

      @ajla it was 30 some yrs ago that GM brought out the 4-6-8 V8 cataracts. And still can't get it right, guess is not quite second time looky anymore, perhaps she need third time looky!

  • Tbone33 Tbone33 on Jul 11, 2014

    This approach to increased efficiency, a relatively minor change to the engine for a minor increase in efficiency which presents many problems, will fail. How about throwing money into developing wave-disk generators for electric engines, or the liquid piston X1 design? High mpg requirements require new technology.

    • Koshchei Koshchei on Jul 11, 2014

      I completely agree about the idea, although I'm not familiar with the concepts you're referring to. Ultimately the biggest issues with current ICE designs are parasitic losses from the spring-loaded valve-train and suboptimal combustion conditions brought about by a variably sized chamber. Fix one of these issues with a cheap and reliable solution, and revolutionize transportation.

  • JimC2 JimC2 on Jul 12, 2014

    A common method of cylinder deactivation is practiced by some of the local yokels, living in my area, who drive vehicles powered by V7 engines. This is an engine that left the factory as a V8 but was given only cursory maintenance over the years. These engines are quite popular in 20 year old pickup trucks and Camaros around the trailer parks.

  • DrGastro997 DrGastro997 on Jul 12, 2014

    I had cylinder deactivation on a MB V8 E430 Sport. It caused more problems for that MB money-pit. I personally want all my cylinders working at all times... R.I.P E430

    • Blowfish Blowfish on Jul 14, 2014

      i suppose when u blow 80-100k for a car and whats the 2-3 mpg going to cost u? those stop when stopped engine are great as its kind of stone silence when stopped, but I am not crazy about the shaking when re-start again. Thats the thing I guess nobody can avoid yet.