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Cruising A/F ratio?

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Old Oct 18, 2005 | 07:14 PM
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Cruising A/F ratio?

I have adjusted my A/F according to the self help posts here but have found little offering on what people are finging their cruising A/F ratios. I have noticed mine in the 14.0-14.3 range.
Should I be adjusting my ratio to be in the 10's during my low throttle range as well or is this OK?

Please advise.
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Old Oct 18, 2005 | 07:18 PM
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Originally Posted by blkdinan
I have adjusted my A/F according to the self help posts here but have found little offering on what people are finging their cruising A/F ratios. I have noticed mine in the 14.0-14.3 range.
Should I be adjusting my ratio to be in the 10's during my low throttle range as well or is this OK?

Please advise.
crusing should be as close to 14.7 (stoich) as possible. If you cruise in the 10's your going to be wasting a ton of gas.
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Old Oct 18, 2005 | 07:55 PM
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Thanks
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Old Oct 18, 2005 | 07:55 PM
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14.7 should be ok as long as you are in vacuum
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Old Oct 18, 2005 | 08:00 PM
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Im About 14.9 15.1 @ 3,000 Rpms With No load. If I give a little gas it will go 2 14.1 or so.
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Old Oct 19, 2005 | 05:51 AM
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I cruse in mid 15's in vacume area's. EGT's don't go up too much but makes for good fuel econ if I can keep my foot out of it.
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Old Oct 21, 2005 | 05:54 PM
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From: houston
the 02 sensor is in complete control of a/f ratios during cruising and most part throttle, and any adjustment you try to make will have no effect. You can only make adjustments to the "fuel maps" with external fuel controllers, and these are not accessed until higher engine load. It's the difference between open/closed loop control.

Only make fuel adjustments during WOT and positive boost pressure, let the 02 sensor do it's thing during cruise conditions, and the 02 sensor should be trying to control at 14.7, which is perfectly ok for cruising.
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Old Oct 21, 2005 | 07:02 PM
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doen't it depend of what emu he's got? I certainly have complete tuning control of the fuel on my car.
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Old Oct 21, 2005 | 07:30 PM
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From: houston
Originally Posted by nothere
doen't it depend of what emu he's got? I certainly have complete tuning control of the fuel on my car.
you might want to check with your emu supplier instead of taking my word for it.
I think what your engine management supplier will tell you is..... you have complete control of the programmable fuel maps, but you don't have control of the closed loop response from the 02 sensor. You only have control of open loop mode, when the fuel maps are actually accessed. Like I said, don't take my word for it, ask your EMU provider.
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