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I was thinking about putting together a road load force calculator, probably using php, maybe I could include a graph to illustrate the increase in power needed to go various speeds? The inputs would probably be Cd, RR, weight, air density (or average elevation), and possibly change in elevation (if it's for a round trip this is zero). Would anyone be interested in this?

Hi Lyeinyoureye:

___Take a look over Wayne Brown’s Prius II Sim for both Palm and what looks like now a PocketPC build for an idea of what has been completed already.

___You can find his excellent work at the following web address: www.privatenrg.com.

___I remember reading a lab paper about a year ago on the multitude of input equations describing each separate load to come up with a relatively solid total load output that may be able to deduce FE. The equations on the surface appeared to be plug and chug but that does not make this an easy task. Reading about Wayne’s work from years past, he has modeled some of these inputs himself and there in lye’s the tough part. What I would do is speak with Dan (Krousdb) as he is a personal friend of Wayne’s to see if he could model a non-hybrid or diesel. This project has to be easier then modeling a Prius II with the various maps of MG1, MG2, and ICE RPM interacting at a given speed to produce a given load to back fit to a given FE besides all the variables that Wayne has already calculated the various loads for. I would be making a WAG but let us assume the wind, terrain, elevation, HW, and type of road you are currently driving can be changed by a factor to match a given automobile vs. doing the model from scratch? If so, Wayne would only need the RPM vs. torque curve and possibly Fuel consumption along it to calculate everything. Wayne Brown would be the guy to contact about this given the magic that he has previously performed …

___Good Luck

___Wayne

Whoa! Talk about a complete program, that's way more indepth than I what I was thinking of, which is something close to simple glider model/calculator so that people could get an idea of how drag, rolling resistance, and weight are related to fuel economy and speed. What'd be really neat would be to take Wayne's work and use that as a backbone for an entire database of vehicle model specifications. Although I'm not sure where all the data needed for such an accurate analysis could be found? I'll send him an email tonight, thanks a bunch!