What's the best RV/motorhome aerodynamically?
 

Considering stock (especially used) recreational vehicles and motor homes, which ones have the best aerodynamics?

Vixen
 

To my knowledge,the distinction would fall with the Vixen,long dead now.
Relying on memory ( risky ) with her TD BMW 5-cyl she could knock down around 21 mpg in real highway driving.
The roof tilted up for overnight stays.No Cd was published.I would have estimated it at 0.30 or a tad under based on FKFS Omnibus images from Germany.Maybe Cd 0.27.

Check this out:

http://citeseerx.ist.psu.edu/viewdoc...=rep1&type=pdf

Esp. see configurations G and H, with CD <0.25 and wheels/tires not optimized, plus sharp roof edges. Basic brick with wheels, streamlined.

The GMC units from the '70's were wind tunnel tested.

http://i146.photobucket.com/albums/r.../IMAGE_062.jpg

I'd say the Dodge/Mercedes diesel van units will be the ones to beat due to efficient drivetrains and relatively small frontal areas.

good recall on the vixen Phil, here's a link
http://ecomodder.com/forum/showthrea...5mpg-4836.html

I know that this will sound bad, but if you are into ecomodding, a school bus with a diesel cummins 5.9 will get 11-12mpg without any modifications. I think that with some minor expenses, you can make a pretty sweet bus that gets 15mpg or better. We got ours for $2200. Keep in mind that this is a 38 foot engine forward flat windshield aero hog with no mods.

What's the best RV/motorhome aerodynamically? The one you modify the most! ;)

that is one of the reasons that I suggest a bus. Cheap to get, good running gear, and most of the time if you have a major failure, you can sell parts off it for as much as what you paid (in my case).

On the other end of the spectrum might be a diesel westfalia camper, maybe good for 30mpg, dunno.

course if you just want a place to stay dry and keep the bears off ya, then a mat in the back of your hatchback (passenger seat forward) can be relatively comfortable.

And a jungle hammock fits nicely on anything from a bicycle on up and is quite dry and comfortable.

Though it would be interesting to see an eco'd bus :)

It depends on your requirements. Where do you want to take it? How much ground clearance is needed to get in/out of camp sites? How many creature comforts are must have? How many people will be sleeping and eating inside it? How many days of food, water and restroom capacity do you need between stops? How many miles do you need between refueling stops? If traveling lots of toll roads, how many axles can you afford? What other dollar or weight budget restrictions might be involved? Don't forget all cargo needed to enjoy the trip and/or destination. If you go somewhere and drop anchor for a spell what kind of auxiliary mobility will you need to get around? These factors may have a higher effect on your satisfaction than how many MPGs you get.

BTW, I can meet (even exceed) the EPA highway number on the sticker of my (stock) truck towing this (aerodynamically stock) trailer including extras.
http://kamperbob.com/EU3kReceiver/GenMounted.jpg

You can learn more about this genre of small car/truck friendly RVs at Egg Central.

Cheers
KB