ITB, closed loop lambda control load type

Hi

When running ITB's should all load based maps be switched over to TPS instead of MAP, for example the when using closed loop lambda control the default table is using MAP as it's source in mtune.

Or will I need to experiment to find out what the best source is per table/map?

Thanks

Is it boosted or NA? If its boosted then MAP or similar will definitely be needed for at least Ingition advance and lambda targets etc. If it is NA with mild/stock cams and the MAP sensor is connected to a common manifold then MAP will often give a more realistic indication of engine load. In that application I often use MAP on the ignition table as you can then get the ignition advance optimised under most conditions with much less cells than would be required to achieve the same via alpha-n. In most cases I leave all fuel related tables referencing TPS, that is not to say because it is proven to work the best on all of them, but the main fuel or VE table will usually work the best referencing TPS, and for the others I just find it easier to "see" trends and also cross reference say the fuel table with the lambda target table or closed loop lambda corrections if they all reference the same load.

In the case of a NA race engine with large valve overlap etc then I will usually not reference MAP at all for any of the common tables, it is usually too unstable to be useful as a load indicator. Sometimes I will still have it used as a multiplier in the fuel equation, especially if there is an intake restrictor or bad airbox design.

For closed loop corrections on steady state I find that MAP signals are stable enough to use as a table axis - transients are another story ;)

Thanks guys. It is a stock NA 1200cc motor from an old goldwing(1985).

I do have a resonance chamber as well, so I’ll ignition with MAP and fuel related with TPS to start with.

Thanks again.