How to expand spark table

[Lakegoat]

On a E67, 12611938, spark airmass is not underlined so I cannot change those numbers. I have a boosted application and I would like to expand from 1.36 to 2.00. Is that possible?

[blindsquirrel]

Yes, by airflow scaling.

But you should make sure that's something you want to live with and also if it's truly worth it. My question has always been: In most combos, what do you gain by getting fine control over the range where spark will typically be only one value across a whole range of cells, that makes it worth giving up resolution that costs you the fine control over the lower load/lower speed areas where you really do need the fine control? WOT is easy (see also: 'locked-out distributor'), part throttle light load is hard.

[Lakegoat]

That's what I wanted to hear. I don't want to modify all of the airflow tables. I looked at my E38 spark table that controls the same engine now and it is pretty much flat at the higher boost and rpm range. I may drop the 5800 to 7000 rpm cells by .5 degree for a little safety. Thanks

[Alvin]

In a pinch

With a 2 bar OS. Commanded a different EQ for more boost.

use the PE spark adders to pull timing for that EQ.

[Lakegoat]

So use the GAS table---rpm vs eq to pull timing in whatever cells that I need to ? That would give control up to 1.50

[Alvin]

So use the GAS table---rpm vs eq to pull timing in whatever cells that I need to ? That would give control up to 1.50

Yeah but that would mean you are running some crazy rich AFR too.

There is not a ton of control here.. but the idea is like this..

Low boost command 12.2 AFR 0 in the PE Spark adder
high boost command 11.0 AFR -4? in the PE adder

Does that make sense?

All of this is a bit like picking at fly shit.. Most people don't absolute optimize timing for anything other than full boost and then sorta interpolate down.. They aren't pushing for every degree of timing at every lb of boost.

[07GTS]

just looking into this and im wondering if u can use the static retard airmass [ecm2785] and [ecm12785] to remove timing above a desired airmass as then u can set the ''enable above'' airmass value to anything by the looks of it, that way u can keep a little more in down lower then just remove it in the higher boost ?

[Lakegoat]

Alvin, I had to wait until this morning and read this again. My brain was scrambled. Yeah, that would be good use of that table, I will try that when I get this swapped.