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Nissan Motor Company has announced a new type of gasoline engine

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Re: Nissan Motor Company has announced a new type of gasoline engine

#151

Post by sdwisely » Tue, Aug 16, 2016, 2:58 PM UTC

fgonzag wrote: post #149

semi-extrinsic wrote: post #146

Earlier quoted context omitted.

Modern engines (as in, post 1989) will sense an engine knock (or a misfire) and go into open cycle ECU mode, ignoring the lambda sensor inputs. It'll run really rough and rich in order to avoid any more knocking, which could seriously damage the engine.

And to those curious on how it senses it, they literally stick a microphone in the engine calibrated for the ping (knock) frequency.

that actually sounded like such a low tech solution that I wasn't sure if it was some kind of joke that was going over my head.

Thanks for sharing, that's actually really fascinating.

the patent for anyone interested: https://www.google.com/patents/US4040294

Re: Nissan Motor Company has announced a new type of gasoline engine

#152

Post by gcb0 » Wed, Aug 17, 2016, 6:35 AM UTC

TylerE wrote: post #10

gcb0 wrote: post #8

Earlier quoted context omitted.

absolutely every company has one of those. I'm familiar with the bmw one: VANOS something. from the 90s. variable compression is nothing new, just very prone to failure. the other downside was it was much harder to work on the engine, but nobody cares about that anymore.

No, that's totally different. That's just variable cams(e.g. what Honda calls VTEC). This is actually changing the combustion chamber geometry.

so a lot more complexity to just change the volume inside the chamber in another way?

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