REQUEST FOR INFO: need help on injector trim table operation

[rcdash]

Dear Engineering Personnel,

I'd like to use the injector trim tables to selectively disable fuel injection in cylinders in a progressive fashion as wheel slip increases. My thought was to program each cylinder to cut injection by -100% if wheel slip exceeded a threshold value. I am concerned about 2 things:

1. Will -100% trim completely cut fuel? I don't want to create a lean burn condition in a cylinder.
2. Is there a way to prevent interpolation so that I don't get partial fuel cut? For example if I set fuel trim to 0% for 0% wheel slip but have it set at -100% for 10% wheel slip, what happens at 5% wheel slip? Perhaps I need to create a column before fuel cut is desired and set it to a value just below the threshold (so -100% fuel at 10% wheel slip, but 0% fuel at 9.9% wheel slip)? Can interpolation still occur (e.g. what is the precision of the decimel points - can u have 9.99% wheel slip?)?

I do want to be able to predict exactly what will happen.

[rcdash]

BUMP! This is a great application for the 2D trim tables - I can see it as a great traction control system... No one has thought of this? It could also be a very cool economy tool - cutting fueling to cylinders at very low load/cruise situations...

Where are the programming/techie gurus?

[Ignition]

Trim doesn't cut, it removes a percent - potentially leading to lean condition. Sounds like you want a traction control setup like the soft-cut revlimit, where it progressively cuts cylinders. Not possible currently that I know of. An ability to create custom tables would be ideal, though I realize that is a LOT of work for the software/firmware guys so would not hold my breath.

[rcdash]

Trim doesn't cut, it removes a percent - potentially leading to lean condition. Sounds like you want a traction control setup like the soft-cut revlimit, where it progressively cuts cylinders. Not possible currently that I know of. An ability to create custom tables would be ideal, though I realize that is a LOT of work for the software/firmware guys so would not hold my breath.

And -100% would mean what exactly? That's all I'm asking... While you might think it's a lot of work, I think the trim table could do it as-is, just remove interpolation. There's a lot of flexibility with the way this unit is designed - you just need to think outside the box!

[Ignition]

Oh I agree. Chuck your idea into the Feature Request section with a link to this thread and we might see it pop up one day.

[rcdash]

Just to clarify, this thread is NOT a feature request. This is a request for information on an existing function. Thank you.

[Hal-IP]

Quick update- I have been in contact with rcdash regarding this and he has been provided some controlled tests to verify operations. Will report back with findings.