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Myth Or Fact?

sobeksminion
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sobeksminion Enthusiast

sobeksminion

Posted
Posted

Sorry to keep bothering everyone with the questions.........

I met a bloke the other day who used to to a lot of work on the early skylines/datsuns. He was saying that my 1984 MR30 skyline had probably gained ten or fifteen bhp as the previous owner replaced the exhaust meaning that the emmissions control system had been ditched which allowed for much smoother airflow because the car(in his words) 'isn't trying to eat it's own shit'

What do you guys reckon?

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Factory 5 Mentor

Factory 5

Posted
Posted

"eating own shit" refers to the EGR system, Exhaust Gas Recirculation

Which actually varies between different setups, but sometimes the engine can make MORE power with the EGR gear left on.

The exhaust does still contain some unburnt fuel/air mixture. enough for some turbo engines to NOT have the need for extra fuel enrichment on boost.

An interesting read:

http://www.autospeed.com/cms/A_110577/article.html

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BensDR30 Experienced

BensDR30

Posted
Posted

Also have a read up on HCCI http://en.wikipedia.org/wiki/Homogeneous_c...ession_ignition. As much as we generally 'hate' EGR, it is a fundamental part of the prototype HCCI engines being developed at present. And some of the things that they can do are pretty cool.

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