http://ecomodder.com/forum/sho...95-ford-e-18151.html

Quote:
Getting up at 3AM to beat the heat and wind, we (my wife insisted on going, she thinks the boat tail is great, how cool is that?) drove from Tucson to Phoenix, which is about 1,000 feet lower elevation, to Apache Junction, a total distance of 135+ miles, one way, with lots of subtle hills and valleys in between. We didn’t use the A/C and we ran right at 57-58mph, since that is the ‘sweet spot’ for this drive line (7.3L turbo diesel Ford, A4OD auto trans, 4.10 tail gear).
The drive up yielded 17.26 mpg, compared to an average of 13.1 for the same trip sans the boat tail. I have to say by the time the tail was completed I was having my doubts this would make much of a difference so I was really happy with that. The return trip we used the A/C the whole way, and had an intermittent crosswind of about 10 to 20 mph and got 14.68mpg. That works out to a two way average of 15.97mpg!

see pics

Good morning, Doug Smiley;

Sir, that is impressive. From the numbers you provided, I calculate a 32% improvement in fuel economy without the air conditioner running.

While it may look funny to a lot of people, it does seem to be effective. Congratulations, sir.

Enjoy;

Ralph Javins
Latté Land, Washington

See TRAILER TAIL
http://www.stemco.com/product/trailertail/

https://en.m.wikipedia.org/wiki/TrailerTail

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