leSharo RV
 

I have a leSharo RV that I want to get better mileage. It has been converted to a Buick 3.8 v6 and a a 4t60 transmission with a 2.87 Final drive ratio. It has 1630 RPM at 65 mph. It has 205/85R14 C tires at 60 psi and weights 5500 lbs, 6500 lbs gross. It has only a 15 gal fuel tank. Last time I drove it it got between 15 and 17 mpg. Today I blocked off around the radiator with foam and put a belly pan from the front bumper to the front tires.

It looks like this without the roof mounted AC unit.
https://upload.wikimedia.org/wikiped...front_left.jpg

Supercharged 3.8? If not, having one should help.

Gas mileage seems pretty good, considering!

The similar Vixen RV came in a 30mpg flavor (check that rig for ideas)

My guess is with that motor and transmission all you can do it keep slow and coast often.

NA, predates series II SC.

SC would reduce gas mileage, would be a ton of work for no gain..

Yes, I could install a BMW tubodiesel in the back and trim the roof a foot, lower the floor, take the Buick FWD drivetrain out and put a popup roof on.....not really.

Air curtains and skirts. A blister across the top front to soften the curve.

The big problem is that maybe 20% of the frontal area is at the C-pillar. Graft a second door frame on aligned with the full width for the door to close against on the original hinges.

Or you could of used the 20mpg datapoint of the higher fixed roof Buick 3800 powered vixen “limo” as being a good indication that 17mpg for your rig is about all you can expect without extreme prejudice

Sounds quite surprising that you managed to get a transverse engine and transmission. AFAIK the Renault Trafic had only been fitted with longitudinal ones. On a sidenote, the stock manual transmissions on them could handle a small-block V8 quite easily.

Ditch that roof A/C unit. We often use a portable A/C in our camper. It exhausts out a window and will run on our 2000 watt generator which won't run the rooftop unit. Seems to cool it just as well as the roof unit and as a side benefit is much quiter.

Pay attention!

The 3800 unit is pretty efficient; can't you just go 55 or maybe even 50 to see what it does?