Question about open loop EQ ratios and gain settings when tuning in VE

[cc-rider]

Question for you guys...
When you are tuning in the VE table with the AFR error method, do you set all the open loop EQ ratio and gains to 1 across the board? Everything in the red box in the picture below?

I've read a tutorial here on HPT that says to do this. But I'm not sure why this is needed because the AFR error is factoring in the commanded AFR...so why would it matter if IVT or ECT gains are moving it around a bit?

OL.jpg

[cc-rider]

Any help here fellas? Could really use some advice on this.

[tramotorsports]

I usually set fueling to a 1 above 140*. Easier to do that than chase a moving target imo.

[schpenxel]

Leave lower/cold startup areas alone. Higher areas you can set to 1 for OL tuning.

[Michael_D]

I believe the theory behind setting the modifier tables to 1, is to prevent them from changing fueling while you are trying to calibrate the VE table. Sounds like a great idea, provided that the environmental conditions remain unchanged: IE, the car is in a shop. For street tuning, I'm not so sure. I have had better results using STFT / error.

[mowton]

Leave lower/cold startup areas alone. Higher areas you can set to 1 for OL tuning.

^^^^^ Agree

Leave the area's below 147F IVT and 176F ECT stock to assist in cold start enrichment. Open loop tuning is my preference because it precludes chaning the trims and more importantly the E38 rich after flash is almost a non-issue in open loop...a lot less frustrations :-) The only issue is you need a wide band (which you should have anyways to do WOT tuning) and if you are going to use the trims (which is fine as well) use one of the built in parameters 1) If LTFT disabled -- STFT (average of both banks) or 2) if LTFT enabled -- the LTFT+STFT (average of both LT and ST). Also don't forget in all cases to reset the trims through the VCM control before each scanning session

Ed M

[cc-rider]

Thanks for the input on the open loop tables. I appreciate it.

I've got a wideband and I'm tuning via AFR error method rather than trims. One question I did have about this. I don't see anywhere where I turn off STFT's? (E38 upgraded to 2 bar OS). I see where I turn off LTFT's and have done so. But I don't see any sections for STFT. Am I missing something here?

In my open loop VE tuning data logs....I've got no LTFT or STFT activity. So I'm 99% sure that STFT are turned off. But I was just wondering.

[rao]

I'm not sure why they would need to be changed at all. You are comparing commanded AFR to WB AFR; what the commanded afr is doesn't matter so long as you know what is being commanded.

[mowton]

Open loop will disable the STFT's....again good idea to reset trims before each logging session...belt and suspender protection.

Ed M

[cc-rider]

Got it. Thanks Ed.