A way to cheat and fix your strims/ltrims using Rtac Very quickly.

[TFZ_Z06]

Hello:

A little disappointed that as a dedicated user of EFILive, I never received any response to the question of utilizing Strims to 'smooth' the VE table via Roadrunner RTAGS

A number of us are new users to RR, and any information that someone can share to maximize its phenomenal capabilities is always greatly appreciated.

However, I understand people are busy and my follow-up is to simply confirm that the method is still applicable.

While unable to utilize the VE Fixer through RTAGS , it can still be done manually (as the post indicated).

Utilizing SHRTF pids, just used the following calculation:

SHRTF1+SHRTF2/100+1.

After logging, and applying the 'standard' filters (TPS, DFCO,etc), and utilizing the EFILive MAP function, simply cut and pasted it to the VE Table.

Definitely 'smooths' out the VE Table, and after a few passes it has nearly zeroed them out.

Hopefully the RTAGS method for VE Fixer will reappear at some point.

If I missing something, please let me know.

Thank you very much.


..WeathermanShawn.

I am an RTACS user. I have tried updating my VE via this method and the results were not acceptable. It is my opinion, based on testing, this method will be largely affected by the cam overlap in use. In my case, it did not work well with stoich settings at 14.68. In retrospect, I would wonder if setting the A/F richer might have helped.

This would not result in correct data.
SHRTF1+SHRTF2/100+1.

Try:
( ({SAE.SHRTFT1} + {SAE.SHRTFT2}) /2)/100 + 1

or: Note, my stock car was usually around 5% LTFT and ran good as tuned by GM, so
iff ( ({SAE.LONGFT1}+{SAE.LONGFT2})/2 > 5, ({SAE.SHRTFT1} + {SAE.SHRTFT2})/2)/100 + 1, 1)

Also note, you may want to control what happens at if FT < 0 w/formula.

[WeathermanShawn]

Thanks for the clarification on the formula.

Interesting point on cam overlap and some of the difficulties you mentioned. I will definitely try out the points you mentioned.

[TFZ_Z06]

Thanks for the clarification on the formula.

I either got lazy transposing the formula, or I made an error in my calculations.

I will re-do the calculations.

Interesting point on cam overlap and some of the difficulties you mentioned.

I will definitely try out the points you mentioned.

Again, thanks for a double-check on the formula. It was a long weekend. Glad to have someone keep me from using bad data after all that effort.

Thanks again.

..WeathermanShawn..

Shawn, I can appreciate your background and have enjoyed reading your previous posts. I know you are kicking yourself on that one. Please post your observations from using RTACS. There are not that many of us, so I'm always looking for ideas from real time users.

REGARDING OVERLAP:
I haven't spent enough time on this, but subtle ques from datalogs lead me to believe that A/F at idle should be up almost 1 A/F point from stock to get the correct readings while in SD, OL mode. (Where resulting A/F = exhaust O2 + overlap O2).

[WeathermanShawn]

Probably need to do a better job of properly documenting findings, especially as it relates to RTAGS. Problem is there really is no official 'book' on tuning, especially as it relates to EFILive and RTAGS.

Have done some experiments while driving (with assistance). Changing RPM thresholds for airflow calculations (MAF), changing VE, MAF sensor calibration, etc. Easy to see in essence how much more the MAF controls airflow calculations/hence fueling calculations at various RPM's, especially above 2000 RPM's. Chased down spark knock in seconds, not minutes.

Sounds like you may have made some of the same observations. I was intrigued by your observations of idle A/F readings 'bias'. Some have mentioned it, but always nice to get someone to quantify it. Makes a lot of sense.

Thanks for your comments.