Proper Way To Lean Or Richen Afr?
Sep 30, 2006, 12:57 PM
#1
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Proper Way To Lean Or Richen Afr?
What is the correct way to lean or richen the afr maps? Do we just alter the data in the cells of the High and Low AFR maps? Or do we have to screw around with any other parameters, ie; fuel enrichment, etc?
Oct 3, 2006, 05:27 AM
#4
Originally Posted by Dus10
What is the correct way to lean or richen the afr maps? Do we just alter the data in the cells of the High and Low AFR maps? Or do we have to screw around with any other parameters, ie; fuel enrichment, etc?
Keeping the intake and injectors stock will make it easier too
Bottom line: if your getting good track times (or your car is fast with low knock counts) without any "service engine" faults, and also have a pleasant drive through city traffic with AC blasting on a hot day with the same tune, your doing something right.
Oct 3, 2006, 07:24 PM
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I have all the data logging equipment including wideband; I want to get my AFR numbers around 12.5 and then retard the timing to compensate for any knock (if there is any). I know i can alter the target AFR #'s in the fuel maps but I wasn't sure how much of a role fuel enrichment plays and any other variables that I don't know about.
Oct 4, 2006, 08:07 PM
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Oct 4, 2006, 08:27 PM
#9
In a normally aspirated car 12.5 is what you should shoot for. I think you will find timing makes more power than a perfect AFR. Without WI or the like, timing would be so off you will be way down on power trying to reach 12.5.
Remember too late timing will also cause knock.
if you read between the lines he acknowledges why Mitsu dumps so much fuel. It may not be efficient, but it is safe. IF you really want better AFRs add water
Remember too late timing will also cause knock.
if you read between the lines he acknowledges why Mitsu dumps so much fuel. It may not be efficient, but it is safe. IF you really want better AFRs add water
Oct 4, 2006, 08:40 PM
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From link:
"Most engines produce maximum power (with optimized ignition timing) at an air-fuel-ratio between 12 and 13. Let's assume the optimum is in the middle at 12.5."
That is scary language to base a tune on: "Most engines", "Let's assume".
Even if you determined 'optimum' (it would be coincidence if it turned out to be 12.5) and our engine fell under the 'most' heading, this philosophy still relies a lot on fuel quality and consistency as well. But, Mitsubishi has, apparently, considered all types of tuning 'ideas' when they bomb-proofed the mighty 4G63. A friend's Evo blew the doors off mine while he was throwing more knock than Avon at 12.5'ish on 91 and 25(!!) psi. However, I'm expecting him to have to ask me for a ride to work any day now.
+1 for 11.0-11.5
"Most engines produce maximum power (with optimized ignition timing) at an air-fuel-ratio between 12 and 13. Let's assume the optimum is in the middle at 12.5."
That is scary language to base a tune on: "Most engines", "Let's assume".
Even if you determined 'optimum' (it would be coincidence if it turned out to be 12.5) and our engine fell under the 'most' heading, this philosophy still relies a lot on fuel quality and consistency as well. But, Mitsubishi has, apparently, considered all types of tuning 'ideas' when they bomb-proofed the mighty 4G63. A friend's Evo blew the doors off mine while he was throwing more knock than Avon at 12.5'ish on 91 and 25(!!) psi. However, I'm expecting him to have to ask me for a ride to work any day now.
+1 for 11.0-11.5
Oct 8, 2006, 12:31 AM
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Originally Posted by jcsbanks
I find very little gain for running it lean, so I leave it rich and run lots of boost to get performance.
those who insult the black smoke just dont/wont understand
Trav