The V is rated for 25/31 but don't think I ever did that well.
With mixed driving, I've seen a few 26-27 MPG tanks. Mostly highway was never better than 28 MPG.
But w/o the RT4WD, I seem to be getting 30 in town and 33-34 out on the highway. I'm basing this on what I'm seeing on my SG2. I'm not sure, but I think it's pretty close. It's going to take a few tanks to know for sure.
My goal is 35 highway and after I get a good tank calibration, I'll see what some hypermiling can do. I may even hit 36!! Won't know, until I try..
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Regarding the trailer. I think you might want to get some input from the resident experts here, before you get too far into the design..
I think, you might be able to design the nose of the trailer so that it isn't a stand-alone module, but will work with the shape of your CRV in a way that will enhance the overall (CRV+Trailer) cd.
I'm not real sure, but the nose of the trailer might be shaped so that it adds a boat-tail effect to the rear end of the CRV..
I found this pic in my pile of stuff. Maybe can help give you some ideas.
