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purrvert
April 17th, 2007, 07:21 AM
Trying to cure some low RPM tip-in knock. Does B5908 add or subtract timing. To make it easier for us lambda challenged, can the row be displayed in AFR instead of Lambda?

purrvert
April 18th, 2007, 09:32 AM
B5908 subtracts from your timing. Seems to be linked to commanded AFR rather than real. This table is useless for tip-in lean conditions.

joecar
April 18th, 2007, 10:17 AM
B5908 is used to add timing at specific values of EQ vs RPM...

where EQ is 14.63/AFR... (i.e. compared to 14.63 AFR, EQ > 1 is richer, EQ < 1 is leaner)

It is linked to commanded EQ or commanded AFR.

More info: showthread.php?p=26944#post26944 (http://forum.efilive.com/showthread.php?p=26944#post26944)

Also, if you see Lambda units, go and change the fuel units to AFR or EQ...
otherwise there's a few holes that can be fallen into during Auto VE tuning.

purrvert
April 18th, 2007, 10:44 AM
B5908 is used to add timing at specific values of EQ vs RPM...

where EQ is 14.63/AFR... (i.e. compared to 14.63 AFR, EQ > 1 is richer, EQ < 1 is leaner)

It is linked to commanded EQ or commanded AFR.

More info: showthread.php?p=26944#post26944 (http://forum.efilive.com/showthread.php?p=26944#post26944)

Also, if you see Lambda units, go and change the fuel units to AFR or EQ...
otherwise there's a few holes that can be fallen into during Auto VE tuning.


Did a search and that thread did not show for me. So I put 2deg in all of b5908 and it seemed to subtract above idle. I can see were if you decreased the high octane table and then compensated for the reduction in B5908 when enriching it could actually be usefull. Im only dealing with intermittent tip-in knock at low RPM, don't have any issues in boost, yet, pulling 10deg in A0010. But how will this help with the dreaded lean spike? I also work in AFR and B5908 still shows EQ. Quote below from Jesse. Thanks Joe.
"The table will add or subtract timing from the main equasion based off of the commanded Airfuel EQ ratio."