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Old 03-22-2017, 10:56 AM   #35 (permalink)
teoman
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Quote:
Originally Posted by cRiPpLe_rOoStEr View Post
IIRC in spark-ignited engines the EGR is actually more functional than in Diesel engines, since it allows a small part of the crude hydrocarbons usually released along the exhaust stream to recirculate. But presumably if you can make it run leaner enough to decrease the HC emissions to a minimum the EGR valve seems to be a good spot to inject the steam, since the it would be able to provide a cooling effect to the pistons in a way similar to what a richer mixture would.
Diesels can run at whatever AFR they please. Gasoline fueled engines have to maintain a constant air to fuel (or oxygen to fuel) ratio. If you push in less o2 by means of pumping gas with no o2 (exhaust) then you can inject less fuel when power is not needed. So EGR has a bit of an advantage to control emissions and it can have a significant effect on fuel consumption.

I like that injection point. However looking at random pictures of my fancy intake manifold, it does not seem to mix uniformally with the intake air. But i could be completely wrong.

Last edited by teoman; 03-22-2017 at 11:03 AM..
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