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Discussion Starter #1
I know rich kills HP but with stock injectors, EBC tuned in at 14psi max, stock pump, FIPK, My Autometer A/F Gauge (on the front O2) runs RICH. WOT stays max or only one or two ticks from max RICH. How can I bring this down? Or should it be that rich?
 

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WHat is the stock psi on your car?? Usually if you up the boost you will always lean out your fuel mapping. This is good to an extent because the factory specs are for fuel econ. I've seen vacuum leaks cause a serious rich condition. Forced induction cars hate vacuum leaks. Just some place to start.

WD
 

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Twin Power Pellets
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what kind of BOV are you running?

if it's stock... there shouldn't be any reason.. maybe a leak around the y-pipe area.

running rich is better than running lean though :)
 

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Twin Power Pellets
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as far as a 'fix' for running rich...

entry level fuel controllers... most allow fine tuning...

Apexi S-AFC
HKS S-AFC
etc...
 
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Discussion Starter #9
Open atmosphere Apex-i, but that should only be rich between shifts.
 

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The Wizard Of Aaahhhhh's
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First of an A/F ratio meter is pretty much useless at WOT. The A/F ratio meter is simply a volt mater with LED's. The volatage range is only .050V to 1.000V.

LEAN RANGE: Four red LED's (.050 to .249V)
STOICHIOMETRIC RANGE: Ten yellow LED's (.250 to .749V)
RICH RANGE: Six green LED's (.750 to 1.000V)

These ranges are for the Autometer gauge read during cruising conditions. These ranges are NOT correct for at full throttle! A voltage of .75V is rich during cruise but very lean at full throttle.

During wide open throttle (throttle opening greater than 80% as indicated by the throttle position sensor) the A/F ratio will be forced rich by the ECM for maximum power. During this time the oxygen sensor outputs a voltage that corresponds to a rich A/F ratio. But the ECM ignores the oxygen sensor signal. The ECM is now in open loop, and relies on factory programmed maps to calculate what the on time of the fuel injectors should be to provide a rich A/F ratio for maximum power. The A/F ratio meter should indicate rich during this time.

Hope this clears up your confusion. Goto www.gadgetseller.com to learn anything and everything about A/F ratio gauges.



Chris
 
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Discussion Starter #11
I thought Richer meant less power, not more power. I thought that the leaner you can go without detonation the more power you will have.
 

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The Wizard Of Aaahhhhh's
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If I may get on my soapbox for a minute...forgive me if this gets long. :)

An automobile engine will run with the A/F mixture ranging from about 8:1 - 18.5:1. The ideal ratio would be one that provides the most power AND the most economy, while producing the least emissions (for all of you in a state that does testing). But such a ratio does not exist because the fuel requirements of an engine vart widely depending on temperature, load, and speed conditions.

Stoichiometric mixture is 14.7 parts of air to 1 part of gas. This is the ideal mixture or ratio at which all the fuel combines with all the oxygen in the air and both are completely burned. It has been proved that the best fuel economy is obtained with a 15 to 16:1 ratio, while maximum power output is achieved with a 12.5 to 13.5:1 ratio. A rich mixture is required for idle, heavy load, and high speed conditions; a leaner mixture is required for normal cruising and light load conditions. No single A/F ratio provides the best fuel economy and max power at the same time.

If the goal is to get the most power from an engine, all of the oxygen in the mixture must be burned, because the power output of any engine is limited by the amount of air it can pull in. To be sure that the oxygen combines properly with the available fuel, extra fuel must be provided. This increases the air fuel ratio (makes it richer in fuel), resulting in some fuel which remains unburned.

There is a lot more to obtaining max power than just the A/F ratio, you still have to figure in valve timing, ignition timing, volumetric efficiency, atmospheric pressure, and so on.

Hope this made some sense...I'll get off my sopbox now. ;)


Chris


*Edited for typo's*
 
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