Quote: I need to do a write up on AE post 191067 ?
after reading it through it makes a lot of sense. i needed major AE work last year and early this. seems it is going well past 30 days. i want to monitor AE not only by SOP but also with WB02. can you give me some A/F ratios i should be seeing as reasonable along with my SOP? i suspect i went overboard with AE TPS as i falsely(?) worked with it more(200-250%%) so than AEMAP(200-250%) when i started tuning. guess i thought AETPS played a greater roll in a slap down of pedal either when in motion(slow city speeds) or from standing stop(light the tires). after kicking the AEMAP to 300% i saw the effect I wanted. seems i was flowing air easily and needed more fuel(AE). what can you offer as A/F ratio as a function of TPS values or MAP values or possible prior but adjusted for RPM values. like cruise at 70 mph and then see 100% TPS and 95 map. stick 4th of 5 gear. or same but at 35 MPH in 3rd and same TPS MAP. a ballpark is appreciated. WB install coming in a few days(hope).

 

As far as how much AE fuel is required depends upon the conditions and ECM fueling mode. During times of closed loop operation too much AE will drive down the INTegrator and possibly the BLM. In turn this will cause a lean out as the AE tapers off.

If the go pedal is pressed far enough the ECM will enter PE mode. In this case the INTegrator and BLM are locked. So additional AE fuel will not cause a lean out condition.

In the case of a closed loop vehicle I like to set the lower end of delta TPS/MAP AE to be just enough to avoid sputter and not so much that the INT drops. Typically the INT will increase a little then return to normal. This helps with both fuel mileage and emissions.

As the delta TPS/MAP increases the amount of AE needs to be increased. Again, on a closed loop vehicle you do not want it to drive the INTegrator down. In some cases the TPS% for PE entry will need to be lowered. There have been several posts on that topic.

Now, for an open loop vehicle, better throttle response can be had from more AE. Driving the AFR richer then the closed loop 14.7:1 is advantageous. Although for the sake of fuel mileage small pedal motions shouldn't be rich. Only enough fuel to prevent sputtering.

In the case of open loop vehicles and heavier throttle usage I like to go a little richer then the commanded AFR. If wacking the pedal to the floor something along the lines of 12.5:1 may be sufficient (based on a 12.8-13.0 commanded AFR).

Remember though, every engine/vehicle combination is different. In the end it comes down to driveability.

RBob.

Here is a link to the article Ronny referred to:

https://www.thirdgen.org/techbb2/sho...hreadid=249265

 

Thank you.