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Need help explaining this "Requested Engine Load" map

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The map is from my Lexus GS460 that I am trying to tune. I have been trying to figure out what this map means for a while now but unable to. Can some one on this forum help?

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Looking at the axes you have engine torque in Nm and RPM.

Since this table is called the requested engine load table, I would think these values represent cylinder filling.

If you look at the very top bar in your screen shot, there is text saying "allowed values 0-799.98% filling" which makes me think this is cylinder filling or VE.

Looks like Lexus is just using engine torque in Nm as an axis vs the standard MAP value but I think the relationship is the same, higher torque, higher MAP value. They may estimate or calculate engine torque from the MAP signal the ECM receives?

Maybe someone familiar with the Lexus control strategy can chime in and see if I am correct in this analysis.

I'm not at all familiar with the vehicle, but I would suspect it's related to electronic throttle control and the throttle blade/butterfly position.

Some vehicles* are programmed for proportional torque output.

*came across a colaboration between Cummins and EATON a couple of days ago where they had an integrated power unit that specifically stated the electronics controlling the engine and transmission worked together to give the best economy while meeting the "torque demand" from the driver.

How new is that car? Looks to me like a torque on demand (TOD) map. TOD and Force on Demand (FOD) are used by OEM's as a replacement for strictly airflow based requests between control units as well as within control units. There are hundreds of TOD requests that could come from engine/transmission/ABS/stability control/brake systems/cruise control/etc. Probably started in the early/mid 2000's with most.

I'm guessing thetamotorsports is probably pretty close to correct. I've never seen one setup like that with VE as the map values, but without knowing the SW logic I feel like it might be hard to be sure.

@PCE: The car is from 2008

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