I have my VMSpc up and running, displaying engine load, intake manifold temp, turbo boost, and RIM. I am trying to understand the relationships between these parameters, how they affect each other, as well as their importance to engine safety. Can someone please explain these? What other parameters should be monitored? Thanks, Royce.
Royce,
Engine load is mostly a function of your right foot. And, as you would expect it is closely related to boost pressure (more throttle, higher boost pressure).
Intake manifold temperature is a function of both ambient temperature and efficiency of the CAC (Charge Air Cooler), also called Inter-cooler and After-cooler-- all the same beast. Ideally, intake manifold temperature should be within a few degrees of ambient temperature.
I find instantaneous MPG another interesting parameter.
Royce, you can monitor what ever you think is important. It watch transmission temp, retarder temp, oil temp, coolant temp, manifold temp, oil pressure and battery volts with big red/yellow/green indicators. A glance tells me things are OK. Gear, tach, turbo pressure all make a difference in economy and cooling. Immediate MPG gives you an idea of what is going on right now. Recent MPG is a rolling average over time. It changes much more slowly. Everyone drives differently. I usually drive about 5 mph under the limit but not over 65 and not under 55. The biggest impacts on economy is wind, hills and then speed. A moderate drive gets you there soon enough with much less stress.
The gearheads can probably add to this.
Art from VMSpc told me engine HP is calculated, not sure where load and torque comes from.
Roger
Engine horsepower--even on a dynamometer--is a calculated value. Torque and RPM are measured, and then horsepower is calculated.
I find my intake temp will go up as I increase load on the engine. If i am climbing a big hill it will go up about 10 degrees and matches the increase in temps for the coolant as well. I just had my intake sensor changed out as it was jumping around up and down 20 degrees in seconds.
I monitor every engine parameter. I just don't know how they all relate to each other.