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Black LS1 T/A
January 12th, 2023, 04:56 AM
I've time-marked his discussion so you go straight to the recommendation he is making.

"How to setup a base fuel map for larger displacement LS engines"
https://youtu.be/ftoMyfHPxlI?t=41

He's saying copy the table of VE values and update to your new displacement.
(Increasing Displacement in the software scales up the VE vales, as you probably know.)
Then, he pastes the old VE values back into the VE table.

I'm not understanding. If you increase the displacement value, and the VE values adjust as a result, that is not what is intended by software design?


What is the logic behind changing the VE values back to the old displacement VE values? Help me understand the logic. Is he right or wrong?

joecar
January 15th, 2023, 08:49 PM
The displacement value does not affect VE or anything else, it is purely for documentation.

joecar
January 15th, 2023, 08:51 PM
Unless maybe HPT adjusts the VE table based on the change in displacement (I don't know if HPT does or does not do this).

EFILive does not do this.

joecar
January 15th, 2023, 08:53 PM
I don't understand why he pastes the old VE table back in.

Black LS1 T/A
January 16th, 2023, 03:49 AM
I don't understand why he pastes the old VE table back in.

Thanks, Joe. How have you been!

Actually, a lot of guys responded over at LS1Tech and replied that what he is saying is B.S.

Black LS1 T/A
January 16th, 2023, 05:37 AM
Well... the conversation over there is evolving...

https://ls1tech.com/forums/pcm-diagnostics-tuning/1964260-guy-says-keep-original-ve-values-when-increasing-displacement-value.html

joecar
January 16th, 2023, 06:03 PM
Thanks, Joe. How have you been!Hi Michael,

I am well, I hope you and yours are all well.



Actually, a lot of guys responded over at LS1Tech and replied that what he is saying is B.S.
I'll take a look over there shortly.

joecar
January 16th, 2023, 06:17 PM
Your are correct in pointing this out:


EFILive uses the cylinder volume to calculate the VE as a percentage.
Changing the cylinder volume will change the VE percentages displayed in this table.


After he increases the displacement (which causes the displayed VE% to drop), does he paste back the original VE% table (i.e. not the raw g.K/kPa table)...?

Black LS1 T/A
January 17th, 2023, 01:25 AM
Yep.

He copies his VE values before changing displacement, then pasted them back in as a "starting point" for tuning the VE table. Another guy that used HP Tuners a long time backed him up and gave a history of how the software used to use percentages that would change after displacement was altered.