Running lean, high octane, burnt engines
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From: SoCal...
You can richen or lean the mixture with it, plus it will also let you adjust the VTEC engagement point.
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From: SoCal...
More of a bandaid than anything, it will "work" however depending on how much you change it will determine whether you will trip a check engine light. For example if you add fuel pressure when the car is in closed loop the computer will see the extra fuel in the o2 sensor and start trimming the fuel back out via the injector pulsewidth, you can get by with ~5% or so without issue but if you go much more than that and you will get a rich code.
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From: Santa Cruz
Engine=3-4k plus labor
EMS=2k or less plus tune
looks like a motor cost more.
this comes down to a pay to play sort of thing in my book.
not that this helps but I am running larger injectors, adjustable FPR, and a EMS with full tune that does not use the O2 sensor at all.
EMS=2k or less plus tune
looks like a motor cost more.
this comes down to a pay to play sort of thing in my book.
not that this helps but I am running larger injectors, adjustable FPR, and a EMS with full tune that does not use the O2 sensor at all.
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From: SoCal...
Wow, that's pretty damn lean. What kind of dyno were you on and was that using a tail pipe sniffer? I wonder if the sensor may have needed calibrating? I have seen issues when tuning cars on an inertia dyno (mostly dynojet) as well, because the load isn't as high as it would be on the street.
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i didnt think you could add fuel with a vafc
so if u use a fuel pressure regulator you can use it up to 5% and safely add a little fuel to an engine with i/h/e?
the ap2 is fairly lean from the factory i think
so if u use a fuel pressure regulator you can use it up to 5% and safely add a little fuel to an engine with i/h/e?
the ap2 is fairly lean from the factory i think
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From: SoCal...
I have an AFC Neo and it says it allows +/- 50%.
You can change the fuel pressure up to the point where the fuel trims get off too much and trips the check engine light, I don't know the exact tolerance of the s2k PCM before this happens though, on most of the cars I deal with though it's ~ 10% (Mustangs, Camaros, Corvettes etc...). If it's for the track and you are going to be running mostly WOT you could just clear the code(s) before each session since the fuel trims are only used in closed loop.
You can change the fuel pressure up to the point where the fuel trims get off too much and trips the check engine light, I don't know the exact tolerance of the s2k PCM before this happens though, on most of the cars I deal with though it's ~ 10% (Mustangs, Camaros, Corvettes etc...). If it's for the track and you are going to be running mostly WOT you could just clear the code(s) before each session since the fuel trims are only used in closed loop.
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The S2000 ECU is a speed-density system, meaning that fueling rates are determined by engine speed and manifold pressure. If your powertrain is highly modified (say exhaust, header, intake, etc), you will have higher volumetric efficiency, which means greater airflow, but since the MAP reading is the same, the ECU doesn't know the engine is actually getting more air, and won't know to inject more fuel, so it won't run as rich.
As an aside, if our engines used a MAF sensor instead, then it would compensate?
Running lean (actually a misnomer, by 'lean' most people mean running 'less rich') by itself doesn't harm the engine any. 50 C). Heavy knock will eventually damage an engine, however, the stock ECU will use its knock sensor to retard timing and prevent knock, so I doubt that is an issue.
At part throttle, the engine runs in closed loop, meaning it uses the oxygen sensor to run at a stoichiometric AFR.
At part throttle, the engine runs in closed loop, meaning it uses the oxygen sensor to run at a stoichiometric AFR.
Brings up a good point...just what is "lean" vs "rich"? A stoichiometric AFR of 14.7/1 is what? Rich? Lean? Right in the middle?
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What mods do you have? I know on my AP1 (2003) with my lambda installed before the cat it runs quite rich, I've only got fairly limited mods though, K&N FIPK, Berk Header, stock cat and Berk single 3" exhaust.
At Chuckwalla in 3rd gear at 6700 I'm running 12.2:1, 7700 11.8:1, 8700 10.6:1
At Chuckwalla in 3rd gear at 6700 I'm running 12.2:1, 7700 11.8:1, 8700 10.6:1
So, at those AFR's, are they all rich because they are less than 14.7? Still a little confused as to what numbers are rich vs. lean.
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Originally Posted by yonson' timestamp='1335233508' post='21636712
Be warned if the dyno shop uses a tail pipe sniffer they are known to read a little leaner (~.5 - 1 AFR) than the car is actually running because of reversion and the sensor being after the cat. (if you have one).
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From: Orange County, CA
Originally Posted by psychoazn' timestamp='1335234300' post='21636750
[quote name='yonson' timestamp='1335233508' post='21636712']
Be warned if the dyno shop uses a tail pipe sniffer they are known to read a little leaner (~.5 - 1 AFR) than the car is actually running because of reversion and the sensor being after the cat. (if you have one).
Be warned if the dyno shop uses a tail pipe sniffer they are known to read a little leaner (~.5 - 1 AFR) than the car is actually running because of reversion and the sensor being after the cat. (if you have one).
[/quote]
I have a 08.