Johnny5

iTrader: (2)

So when I was on the dyno recently my numbers for my A/F were generally in the 13.4 - 13.9 range across the board (with numbers in the 14 at very low RPM < 3k).

I did some tweak in the PE table and tried to "fix" it. Now I know that the 14.1 commanded is ideal for emissions and from what I found searching 12.8'ish is ideal for power.

Question 1. Anything lower than 12.8 is considered rich and anything above this is lean correct??

Question 2. Lets say I have number in the 5000-6300 range of about 13.3 A/F. When I go in to modify the PE/RPM table what do I need to do to bring them down to 12.8? Is this a multiplication of 100+ or a mult of something less than 100?

Question 3. The numbers or multiplication factors in the PE/RPM table. The higher the number in the table the more fuel or the less fuel?

Quesiton 4. Do you just try to set it at 12.8 across the board because I've seen folks on here say that you want to run the richest (<12.9?) at your Torque peak and then lean it out from there. I assume you don't want to go leaner on the top end than 12.8-13.X?

red ws6 99

The numbers in the PE vs rpm table are figured out by using the following equation:

14.7/PE = AFR Now this assumes you have a correct IFR and MAF table.

I set my commanded AFR to whatever I want in the PE table. My maf table is stock so I then tweak the IFR so the commanded and actual AFR match. Once this is done the computer can compensate for large changes and still keep the AFR correct.

Gary

jimmyblue

iTrader: (11)

My stock PE table was all 1.25s which commands a
fat 11.8:1 AFR. My wideband showed 11.7 (not shabby).
If you were seeing 13.xx with a stock tune then you have
some sensor or table seriously out of cal. What values did
you find in the PE table when you started editing?

Johnny5

iTrader: (2)

I did the " set it to some value of the higher rpm thing" across the board and then reduce while looking for knock. I basically set it to 1.1996 across the board. On my dyno runs it gets into the 1.27- 1.3 range in the higher rpms. The 1.3 netted me somewhere around 2.6-2.7 and the 1.27 was still around 13.2'ish based on my dyno graphs.


AND I set my IFR table to 3.44 across the board if that matters.

red ws6 99

My stock PE table was set for a WOT AFR of about 13. Most of the cars I have seen were set much higher than your 11.8. The only time the cars I have seen would get a 11:8 range would be with COT.

Gary