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Old 06-02-2008, 05:09 PM   #1
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Default Cruise too lean?

Okay, i have asked this question by threadjacking and not gotten a straight answer. Can a very lean (18:1) cruise cause you problems? i.e. burnt exhaust valves or pistions? I do not have an egt gauge
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Old 06-02-2008, 05:21 PM   #2
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Once i cruise at 16:1 the car gets pretty upset...I dont see how you can manage 18:1
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Old 06-02-2008, 05:23 PM   #3
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no bucking whatsoever. my uego often goes - - - while cruising.

great mpg though, over 30
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Old 06-02-2008, 05:24 PM   #4
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^ downhill?
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Old 06-02-2008, 05:24 PM   #5
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all the time.
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Old 06-02-2008, 05:25 PM   #6
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goes back and forth from 17 to 18 to --- and back
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Old 06-02-2008, 05:28 PM   #7
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there's a honda tuner advancing time way up and running like 19:1. Its not a gamble I'm going to take on my nice motor. I'm running at 15.3:1 now and noticed about 2mpg gain...getting me up to a whopping 25mpg now on highway.
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Old 06-02-2008, 05:48 PM   #8
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so, what people are saying is i should get an egt gauge.
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Old 06-02-2008, 05:50 PM   #9
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Once I hit ~16 and crusing on highway I get lean bucking...

I wonder how retarded you have the ignition to get away with that. I'd concentrate on running more timing and ~15:1 AFRs and use an egt to check things.
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Old 06-02-2008, 06:29 PM   #10
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Mine ran off the gauge for while, no issues. Quizzed many people about it and the popular answer is when it get a lean "pop" in cruise fatten it up a bit. I'm 16 or so now.
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Old 06-02-2008, 06:33 PM   #11
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i can run mine pretty lean at cruise too, i'm in the 15-16:1 range right now but it's been 17-18:1 before and seemed ok but i wasn't sure if it would reduce my motors longevity or not. my gut feeling is it won't hurt anything at cruise but i really don't know.
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Old 06-02-2008, 06:34 PM   #12
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lean "pop"? My car pretty much behaves like a huge hand was pushing/pulling it back and forth once I get past 16:1.
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Old 06-02-2008, 09:16 PM   #13
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I'm running an AFR of 17.5:1 at cruise without any problems. I have run it as high as 19:1 at cruise without having any hassles either.
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Old 06-02-2008, 09:20 PM   #14
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interesting there's some that say they can't go past 16:1 and some say 17-18 no problem. i wonder how much has to do with timing
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Old 06-02-2008, 09:55 PM   #15
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im running 16:1 at cruise no problem.
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Old 06-02-2008, 10:25 PM   #16
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what kind of fuel pressures are you all running?

I dont think you're going to be EGT limited at cruise under 4500. just not enough load on the motor...
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Old 06-02-2008, 11:05 PM   #17
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fuel pressure? stock FPR, nothing else.
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Old 06-02-2008, 11:27 PM   #18
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stock fuel pressure here too
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Old 06-02-2008, 11:28 PM   #19
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i ask because I wonder if the guys running >16:1 are getting better atomization from higher rail pressures.

I do ok with 15.5 or so.
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Old 06-02-2008, 11:43 PM   #20
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heres a quick read. according to their rsx, 15.7:1 was the best
http://www.hondatuningmagazine.com/t...ing/index.html

wouldn't the best way to do this be to log duty cycle at 15:1, 16:1, and 17:1 for the same drive at the same speed?
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