ITB: TPS VS Map

Please excuse my lack of knowledge. If it helps this question pertains to the power sports industry and tuning sports bikes. Since these guys have an ITB set up my research tells me TPS vs RPM is the way to tune and the MAP vs RPM is for fine tuning.

I guess my question is:

Does the TPS and MAP table get accessed at the same time?

So for example TPS + MAP Table = result or is it more of an either TPS or MAP Table?

My second question becomes how do I go about tuning MAP VS RPM Map?

If the two maps are combined how do I determine which one of the two tables is causing my lean/rich condition?

Inversely if the two tables are accessed independently how do I determine what map is being used at any given moment and what causes the jump from map to map?

It's plenty possible I'm overthinking this, your help is appreciated!!

You are asking good questions, but not enough details to provide a definitive answer.

It depends entirely on the ECU. Some offer the choice of using TPS or MAP as the load axis for the fuel and/or ignition table. Some offer the ability to use both and "blend" the tables (ie, use TPS up to say 25 or 30%, then use MAP, or allow MAP as a compensation to the main TPS load table).

So, how do you tune -- depends on how the ECU operates -- first job is to understand this, and be sure to tune the proper table in the proper conditions. You'll probably end up interpolating the overlap areas.

Take-away -- pay attention to the operating conditions (RPM, TPS, MAP, Air Temp, Coolant temp), and tune the appropriate table. For example, after you have a well tuned idle condition (Engine at operating temp, TPS at the throttle stop, Air temp in normal range) -- if you notice the engine starts lean, then you tune the Coolant Temp Compenstation -- even though it's tempting do not touch the main fuel table if it's already been tuned.

BTW if you ever make a change and it doesn't do what you expected (at least somewhat) -- stop - undo that change and understand what condition is different from what you were expecting.

Thanks for the response.

My reflashing software is pretty limited compared to the course videos I've seen on here. As far as fuel, I have TPS vs RPM and a Map vs RPM as well as an accel enrichment table. Other than that I don't have the option to change anything but the cell values.

By your answer, it sounds like ill have to play with it and when a change doesn't make the expected difference to step back and evaluate.

If you're thinking of using MAP, either alone or in conjuction with TPS, the question is how are you going to get those values?

If using open TBs, darned if I can see how, but if using a sealed plenum/airbox the TBs are drawing from, you can measure the air mass entering it. Not something I've much to do with, but I believe that last is how many OEM setups do it?

Great info from David and Gord.