Thread: AFR and Timing Tuning (02 Regal GS 223k!!!)

Originally Posted by darkhorizon

I built my own transmission friendly PE vs RPM (vs time i guess) table... It removes the time part and focuses on dumping extra fuel at the shift points.



I do some fancy crap on the turbo drag cars, typically not much if any on SC cars.



PE vs coolant temp is the "main" commanded PE afr table.



I use the narrowband to help... Eyeball the trims to see what direction they generally go and go from there. (between -10 and -6 most the time? subtract 7% and consider it tuned) I have my own math saved off thats usually close enough for me not to ever adjust them after the fact unless someone is paying me alot of money or they are convinced i need spend 3 days working on it and I want to look busy tuning their car.

Remember fuel trims take a few power cycles to learn correctly, so go with a base flash and drive around for awhile... throw the gauge up on the scan tool and glance at it while you are driving around to get an idea of how much adjustment you might want to make... tune WOT/PE a while after you make the IFR correction.

RPM vs time I understand the rpm but how do you know when/where to adjust to in the sec area?

PE vs TPS will having a number of 1.300 up to 20% net better mpgs at all?

How do I go about knowing how far to adjust the injectors 0-100 kpa wise? Also where do these numbers come from? I am sure I can find a few different IFR's charts in random 42.5' tunes.

Is there such thing of the correct IFR chart? Or will there be a baseline that will have to be modified?

Should I set my commanded afr from 11.5 down to 11.2 in Base vs ECT across the whole board?

As for the IRF table. How do you go about tweaking this? Doesn't a bigger number lessen fuel? Is there a general percentage to add onto a stock IFR value for a closer correct rate of 42.5's?