Target AFR values in fuel map?

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airman
 

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Joined: Tue Feb 22, 2011 4:40 am

Target AFR values in fuel map?

Post by airman »

I don't mind tuning from raw value, but as of right now my tune is running quite lean on WOT even though the target AFR values on my fuel map are exactly where I want them. Right now, my "target" AFR values for my WOT boost areas are set to 11.2 (raw value 40, for me), even though I'm seeing around 13-13.5. To get my AFR somewhere in the mid 11s, I have to set my "target afr" to about 9.0. At cruise and idle, the target afr matches what I am seeing on my wideband, so this makes me think that maybe it's a MAF scaling or something else in Nistune that's causing this.

S13
Fully Built Ka-t bottom end, stock head
Turbonetics 60 trim
Ebay wastegate, 12psi
880cc precision injectors
Z32 MAF

I did a brief search but couldn't find anything very relevant! Thanks for help in advance.
PL
 

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Location: Adelaide, South Oz
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Re: Target AFR values in fuel map?

Post by PL »

Have you tried increasing the K value?

PL
HermaN
 

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Re: Target AFR values in fuel map?

Post by HermaN »

As PL suggested, have you properly setup your injectors and setup the K-value? If so you should not need to add so much fuel to the map to get the readings you want.

Could also be 1 or 2 cylinders running lean due to bad/clogged injector(s) which means to get a good average reading of all 4 you need to richen up the mixture. Hence 2 cylinders run lean then 2 run rich which gives a good reading in the downpipe or tailpipe because by that point it's all mixed together so the average across all 4 cylinders is fine even though individually there is an issue.
nissangts
 

Posts: 84
Joined: Sat Nov 18, 2006 4:27 pm

Re: Target AFR values in fuel map?

Post by nissangts »

What is your Latency?
HermaN wrote:As PL suggested, have you properly setup your injectors and setup the K-value? If so you should not need to add so much fuel to the map to get the readings you want.

Could also be 1 or 2 cylinders running lean due to bad/clogged injector(s) which means to get a good average reading of all 4 you need to richen up the mixture. Hence 2 cylinders run lean then 2 run rich which gives a good reading in the downpipe or tailpipe because by that point it's all mixed together so the average across all 4 cylinders is fine even though individually there is an issue.
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