cargo van additions
 

Ram Promaster cargo van, converting to a campervan. I'd like to keep the aero clean, and not make this tall beast any worse than it is. I'm getting about 25mpg, diesel. I'm not going to put the typical awning on it. However, I'm finding it hard to resist the roof fan. They are about 15x15, one would be only 3" high flat top (fantastic fan with flat top), 3-3/4" rounded top (maxxfan standard), the most aero looking one is 5" high (maxxfan deluxe).
Any educated guess as to how much of an impact this will be?

Like that MaxxFan deluxe, aero-design 3-in-1 solution. MaxxFan Deluxe Remote Control RV Ventilator System, Smoke Lid - Maxxair 00-07500K - Vents - Camping World

The maxxfan deluxe is my intended unit for my econoline van. Being able to use it closed or open while in transit plus the aero are my reasons

Maxxfan. There'll be three of them on my travel trailer in the near future. Same for newer solar panels, a different air conditioner and maybe a slew of antennas. In other words, don't worry about it.

Planning engine run time is the game for an RV.

It looks like you're hoping to get 10mpg, I'm getting 25.


I'm thinking the flat top fantastic fan with some extra wind faring would be better than the much taller round top models.

I planned on adding some epoxy over styrofoam fastback tapers behind my roof vents and maybe a 1/4 round cylinder in front, same thing with the awning and plumbing vent.

My tow vehicle only gets 18 not towing so I'm hoping for 15-16 but that's with less expensive 87 octain. If my weight ends up under 3500 pounds I may try it with the minivan which gets over 25 and hope for 20 towing.

I researched those Ram Promasters and the new Ford equivalent. The Ram did seem like a better deal and I like the FWD. Did you get the highest top version? There are 3 height choices right?

Many people still have their objections towards FWD in commercial applications, but that's somewhat pointless. One obvious advantage is the lesser weight of the driveline, while the lower floor also leads to other practical benefits and leaves room for improvements regarding aerodynamics too, since it leads an externally-lower FWD van to have a cargo volume comparable to a RWD one.

I think it's two heights and three wheelbases.

I see the Ford has 3 heights, that is what I must have been thinking.
Then there is this
http://s1.cdn.autoevolution.com/imag...-gallery_9.jpg
So maybe there is just a USA unavailable roof type

I have the high roof. I think there is a taller one that is not available here.