AFR's: ACV/Relief Solenoid/Port Air/ETC clarification
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Rotary Dynamics
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AFR's: ACV/Relief Solenoid/Port Air/ETC clarification
I just wanted to get some clarification on what and when things affect afr's
S4 NA
Idle:
Poppet is open and air is injected into the exhaust ports = raising afr's to lean condition according to wideband
Solution: Remove blue plug off relief solenoid, this dumps air into the silencer in the engine bay providing an accurate AFR reading from wideband
Cruise:
While cruising the ECU/O2 sensor tries to keep a 14.7 AFR.
Solution: To tune at cruise, unplug the O2 sensor
WOT:
No air is duped into exhaust affecting AFR's, stock O2 sensor doesn't affect AFR's.
No solution required since AFR's are read accurately at WOT.
S4 NA
Idle:
Poppet is open and air is injected into the exhaust ports = raising afr's to lean condition according to wideband
Solution: Remove blue plug off relief solenoid, this dumps air into the silencer in the engine bay providing an accurate AFR reading from wideband
Cruise:
While cruising the ECU/O2 sensor tries to keep a 14.7 AFR.
Solution: To tune at cruise, unplug the O2 sensor
WOT:
No air is duped into exhaust affecting AFR's, stock O2 sensor doesn't affect AFR's.
No solution required since AFR's are read accurately at WOT.
#3
Rotary Dynamics
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A bunch of that info I got from various threads with your replies, just wanted to consolidate and confirm.
I don't have a cat so I can probably just remove the plug for an extended period of time with no issues.
Thanks.
I don't have a cat so I can probably just remove the plug for an extended period of time with no issues.
Thanks.
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Rotary Dynamics
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Hmmm, interesting finding: at idle wideband read above 16.00, pulled the blue plug off and it turns out it idles in the high 11's(on a hot engine), seems way to rich for idle.
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Since the O2 sensor doesn't do anything at idle or when you gun it, might as well leave it plumbed in to get good gas mileage on cruise.
I run an eManage, and adjusted the maps for my increased fuel pressure - cutting enough fuel to get it back into the range of the o2 sensor - result: started getting the 14.7 AFR's again as opposed to the 11-12 I was getting.
My idle on cold is very rich, but it rises to mid 12's when it's warm.
I junked all the emissions stuff except the crankcase venting, and run no cat.
I run an eManage, and adjusted the maps for my increased fuel pressure - cutting enough fuel to get it back into the range of the o2 sensor - result: started getting the 14.7 AFR's again as opposed to the 11-12 I was getting.
My idle on cold is very rich, but it rises to mid 12's when it's warm.
I junked all the emissions stuff except the crankcase venting, and run no cat.
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1. the idle is tuned rich to eliminate misfires, misifires = high emissions, so they cant do it.
2. in the book "rotary engine" they have a little graph of fuel consumption at idle with and without the air pump. with the air pump the engine can be run leaner at idle.
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