92silver964

If the DME determines (and executes) timing based on engine speed and engine load, how does it determine engine load? Engine speed measurement is clear to me, but I have searched and not found how the electronics derives "load". Anybody know how it does that? Thanks.

Steve Weiner-Rennsport Systems

Steve,

Throttle position, engine RPM, AFM info, and wheel speed info from the ABS controller, all tell the DME about load.

JasonAndreas

Load (in milliseconds) as an input to the various internal maps is based solely on the output from AFM.

92silver964

Thanks, Steve and Jason. My question was based on a graph I saw in the Bentley 964 Technical Data book (pg 28-5) where load and engine speed are shown as the inputs for the DME to decide on ignition timing. Steve, what I gather from your response is that "load" is a multi-variable input that is developed from the parameters you list. I guess it is the way that the electronics forms a more complete assessment of load, rather than just measuring torque (which is my interpretation of "load"). Sorry if I'm geeking out. Cheers.

Lorenfb

"what I gather from your response is that "load" is a multi-variable input that is developed from the parameters you list."

Not correct, as was mentioned in a previous post, 'load' is determined SOLELY
by the AFM output. And an engine can have a load without the wheels turning,
e.g. as the clutch is initially engaged. Furthermore, torque is an output and load
is an input to a system.