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Old Today, 07:29 PM   #209 (permalink)
JSH
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Adventure Seeker - '04 Chevy Astro - Campervan
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Quote:
Originally Posted by JohnForde View Post
I tested for 55 miles with strong & mixed winds. I sense a small improvement. I got 1.9 mi/kWh. My goal is to get above 2 @ 63 mph. A longer test may establish success.
I still need to tape the door hinges,
Try more acute angles. It is now at 11. I may try 14 & 16.
Smooth the underside.
1.85 mi/kWh to 1.9 mi/kWh is an almost 3% improvement in fuel economy. A manufacturer would be dancing a jig. (That is more than adding drive wheel fairings and hub covers to a Class 8)

Before you make any changes to the tail angles I suggest running again in calm conditions. Strong and mixed winds and especially side winds can really throw off your results.


For those talking about cones and circles - remember this tail has to allow easy access to the rear door.
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