Air/Fuel Ratio recomendations.
01-08-04, 10:39 AM
#1
What R U thinking self?
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Air/Fuel Ratio recomendations.
I will be tuning with my Wide Band this weekend for the first time (been on a dyno before, first time tuning myself)
I know the same A/F is not optimal for power & safety so I was kinda looking for a safe combo of both, with a few questions.
Do you risk detonation at higher RPM rather than lower? or is it all boost related. I hit max boost by 4K, should I run just as rich at 4k as I do at 7K? or can I run for a little more power at 4K (leaner slightly) and run safer at 7K (richer)
I have 2 stages of boost, First stage will be 8-9 PSI, second stage will be 12-14 PSI. How much richer should I run in my scond stage of boost? I assume that risk of detonation goes up based on boost do to more intake heat being created? is this an accurate asumption on my part?
My thoughts right now are
11.3-11.8 ish at low stage of boost around 4K, leaning closer to flat 11.0 at redline on fist stage of boost.
11.0-10.8 ish at 4k on high stage of boost, getting closer to 10.5 by redline at 14 PSI ish?
how does that sound? too lean, too rich? Or shoudl I have a flat level all the way no matter the boost & RPM?
opinions appreciated.
-Robert
I know the same A/F is not optimal for power & safety so I was kinda looking for a safe combo of both, with a few questions.
Do you risk detonation at higher RPM rather than lower? or is it all boost related. I hit max boost by 4K, should I run just as rich at 4k as I do at 7K? or can I run for a little more power at 4K (leaner slightly) and run safer at 7K (richer)
I have 2 stages of boost, First stage will be 8-9 PSI, second stage will be 12-14 PSI. How much richer should I run in my scond stage of boost? I assume that risk of detonation goes up based on boost do to more intake heat being created? is this an accurate asumption on my part?
My thoughts right now are
11.3-11.8 ish at low stage of boost around 4K, leaning closer to flat 11.0 at redline on fist stage of boost.
11.0-10.8 ish at 4k on high stage of boost, getting closer to 10.5 by redline at 14 PSI ish?
how does that sound? too lean, too rich? Or shoudl I have a flat level all the way no matter the boost & RPM?
opinions appreciated.
-Robert
Last edited by Rpeck; 01-08-04 at 10:41 AM.
01-08-04, 11:00 AM
#2
What R U thinking self?
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Okay I did some more searches. I think I know the number I want to shoot for. But I need to know if I want those numbers across the board, or if I can run a bit leaner at stage 1, and lower RPM's?
I read anything below 11.0 is a waste of fuel, too rich.
anything above 12.5 under boost is getting scarry.
I read anything below 11.0 is a waste of fuel, too rich.
anything above 12.5 under boost is getting scarry.
01-08-04, 11:13 AM
#3
I came, I saw, I boosted.
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12.5 is scary!
I wouldn't go over 12.0 on pump gas.
On 93-94 octane, with proper ignition retard, 12:1 is tuned pretty much as lean as possible without getting dangerous.
I wouldn't go over 12.0 on pump gas.
On 93-94 octane, with proper ignition retard, 12:1 is tuned pretty much as lean as possible without getting dangerous.
01-09-04, 01:10 PM
#4
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anyone? can i go leaner at lower RPM's or lower boost levels? or should I stay rich across the board? and how much is there to gain by being a little leaner at less dangerous points?
tuning this thing Sunday, kinda like some input.
thanks,
Robert
tuning this thing Sunday, kinda like some input.
thanks,
Robert
01-09-04, 01:29 PM
#5
Don't go rich all across the all the boost load bands. You will be wasting power.
Your vaccum/boost transition band and your first few psi load points can still be pretty lean, in the 13's- high 12's.
After that I would slowly richen it up, to about low 11's by your max boost. Personally, 10's are too save, are robbing you of power, but that is your choice.
Your greatest risk of detonation is generally at peak tourque.
Also, depending on what dyno you tune on, AFR's will generally be leaner on the street with real load, so keep that in mind
Your vaccum/boost transition band and your first few psi load points can still be pretty lean, in the 13's- high 12's.
After that I would slowly richen it up, to about low 11's by your max boost. Personally, 10's are too save, are robbing you of power, but that is your choice.
Your greatest risk of detonation is generally at peak tourque.
Also, depending on what dyno you tune on, AFR's will generally be leaner on the street with real load, so keep that in mind
01-09-04, 01:33 PM
#6
What R U thinking self?
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Originally posted by eViLRotor
Don't go rich all across the all the boost load bands. You will be wasting power.
Your vaccum/boost transition band and your first few psi load points can still be pretty lean, in the 13's- high 12's.
After that I would slowly richen it up, to about low 11's by your max boost. Personally, 10's are too save, are robbing you of power, but that is your choice.
Your greatest risk of detonation is generally at peak tourque.
Also, depending on what dyno you tune on, AFR's will generally be leaner on the street with real load, so keep that in mind
Don't go rich all across the all the boost load bands. You will be wasting power.
Your vaccum/boost transition band and your first few psi load points can still be pretty lean, in the 13's- high 12's.
After that I would slowly richen it up, to about low 11's by your max boost. Personally, 10's are too save, are robbing you of power, but that is your choice.
Your greatest risk of detonation is generally at peak tourque.
Also, depending on what dyno you tune on, AFR's will generally be leaner on the street with real load, so keep that in mind
tuning with my wideband on the street. Likely 3rd gear pulls. .. 4th will be too much speed.
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