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Unclemeaty · 02-23-2011, 01:18 PM

Its been a bit since I last updated, and boy I should have some info for this thread by now. Thanks to forum members, I've now gone about test/tuning a different way. Instead of jumping right to timing and correction maps, I've 'zeroed' ~%75 of the fuel consumption map to 100 points and kept my timing maps stock. I've also now re-callibrated AF target estimates for my stock WB to esentially be a reading lower than actually - I've focused my stock A/F targets with the stock sensors to 12.2:1 instead of 12.6:1 (In turn, the actual AF should probably be closer to 12.6:1). I'm still waiting on a friend to let me borrow his WB AF metter, so for the meantime I've gone with a target of 12.2:1 off the stock sensors. According to upRev, there are more than one style of stock WB sensor, so you best check the calibration for your own setup!

I left the timing map stock, fuel maps to 100, and worked the MAF map. In areas which were lean, I increased the values by the % of difference. I did this by suggestion of a forum member, and basically whatever the actual AF is, divide by the target to get the percentage in change required referenced by MAF voltage. (Taking actual AF and dividing by target AF gives the approx percentage needing change, then change it at the logged MAF voltage). After about ~10 runs of logging and flashing, I've come up with a great base for which the MAF adjustment allows the ECU to come within 97% of the target AF; all with keeping 75% of the fuel correction maps at 100.

The results are great so-far but I dont know if it made any power difference just yet, but I can say that the car was running over and under my target AFs. Its just about aas stable as I can get it for now.

The biggest thing I've found still is that after a few runs, likely the temperatures get too high (oil?) and the ECU starts retarding timing on me, from ~29 degrees advanced to ~24 at peak power. This issue needs some addressing.

Perhaps via an oil-cooler? I've started a new DIY inexpensive oil-cooler thread here, using a Napa/Hayden engine oil-cooler kit. I'm currently still evaluating a purchase for this, but if it works the savings could be substantial over a formal 370z specific aftermarket oil cooler kit.

Hayden / Napa / Summit oil cooler kit. Anyone?

Any other thoughts as to why ECU pulls timing after a few runs??

02-23-2011, 01:18 PM	#62 (permalink)
Unclemeaty Base Member Join Date: Aug 2010 Location: Atlanta Posts: 203 Drives: 150cc Scooter Rep Power: 14	Its been a bit since I last updated, and boy I should have some info for this thread by now. Thanks to forum members, I've now gone about test/tuning a different way. Instead of jumping right to timing and correction maps, I've 'zeroed' ~%75 of the fuel consumption map to 100 points and kept my timing maps stock. I've also now re-callibrated AF target estimates for my stock WB to esentially be a reading lower than actually - I've focused my stock A/F targets with the stock sensors to 12.2:1 instead of 12.6:1 (In turn, the actual AF should probably be closer to 12.6:1). I'm still waiting on a friend to let me borrow his WB AF metter, so for the meantime I've gone with a target of 12.2:1 off the stock sensors. According to upRev, there are more than one style of stock WB sensor, so you best check the calibration for your own setup! I left the timing map stock, fuel maps to 100, and worked the MAF map. In areas which were lean, I increased the values by the % of difference. I did this by suggestion of a forum member, and basically whatever the actual AF is, divide by the target to get the percentage in change required referenced by MAF voltage. (Taking actual AF and dividing by target AF gives the approx percentage needing change, then change it at the logged MAF voltage). After about ~10 runs of logging and flashing, I've come up with a great base for which the MAF adjustment allows the ECU to come within 97% of the target AF; all with keeping 75% of the fuel correction maps at 100. The results are great so-far but I dont know if it made any power difference just yet, but I can say that the car was running over and under my target AFs. Its just about aas stable as I can get it for now. The biggest thing I've found still is that after a few runs, likely the temperatures get too high (oil?) and the ECU starts retarding timing on me, from ~29 degrees advanced to ~24 at peak power. This issue needs some addressing. Perhaps via an oil-cooler? I've started a new DIY inexpensive oil-cooler thread here, using a Napa/Hayden engine oil-cooler kit. I'm currently still evaluating a purchase for this, but if it works the savings could be substantial over a formal 370z specific aftermarket oil cooler kit. Hayden / Napa / Summit oil cooler kit. Anyone? Any other thoughts as to why ECU pulls timing after a few runs?? Last edited by Unclemeaty; 02-23-2011 at 01:26 PM.