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Old 07-29-2019, 02:07 AM   #11 (permalink)
Master EcoModder
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spyder2 - '00 Toyota MR2 Spyder
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Old news, that video is from 2016. They definitely haven't gotten this to work. I would imagine high power consumption is the main problem.

Multiair is the best system on the market right now. It's basically fully hydraulic valves. The problem other manufacturer has dared to use this. You would think that with the complexity of a hydraulic valve lash adjuster and cylinder deactivation mechanism that someone would've thought putting full hydraulic control would be easier.

If you look at the best new engines (Toyota Dynamic Force and Mazda Skyactiv-X), you'll notice they have very primitive cam phasing VVT, and use high volume cooled EGR to cut pumping losses down. Fancier fuel injection systems allow good fuel-air mixing without the need for different cam profiles. If you want to spend more money, Honda shows us it's not very hard to tack on a second cam profile to squeeze out a little bit more.

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