Partial Tonneau cover on pickup (plus cab extension - cab wing)

[KamperBob]

Originally Posted by kach22i

I know this is an old thread, but this is really nice.

Thanks. The short cap project was fun and the end result has been useful for over 5 years now. That particular truck was totaled a few years since and its successor was full size (Tundra vs Tacoma). Even though not full cab width it's a "good enough" gap filler to help aero wise. Since I started full time RVing with the rig this year the storage became a huge plus. Next up for that project is an adjustable deflector on the short cap so it's definitely still a work in progress.

[kach22i]

Originally Posted by KamperBob

Next up for that project is an adjustable deflector on the short cap

I saw in another forum where the leading edge was not flush/sealed and the owner was not happy with the results. Everyone in that forum pointed out the flaw.

Could you just leave the glass lid open and have that act as a RV deflector?

Slide Hitch/Short Cap

[KamperBob]

Originally Posted by kach22i

I saw in another forum where the leading edge was not flush/sealed and the owner was not happy with the results. Everyone in that forum pointed out the flaw.

Could you just leave the glass lid open and have that act as a RV deflector?

Slide Hitch/Short Cap

In respect to this thread please see http://ecomodder.com/forum/showthrea...-rv-19601.html for more on the topic of my project.

[Mandilon]

Would 'the rear half' of my Lady Bug 'shell' improve or worsen the results?

[aerohead]

Originally Posted by Mandilon

Would 'the rear half' of my Lady Bug 'shell' improve or worsen the results?

We'd really need a true-length image for both elevation and plan-view.'just not enough information in the orthogonal view.
It's a beauty though!

[Jeff M]

Originally Posted by aerohead

The 1/2 tonneau was good for 5% mpg on the T-100,D-100,Chevy Silverado,'93 Toyota truck,and a F-150 4 by 4.With a "blister" which is like the back portion of the aeroshell mounted atop the 1/2-tonneau,mpg was 8% better on the T-100.If you combine it with the first 20-24-inches of the aeroshell(Ford Motor Co. calls this a "sail panel"),you can pick up a combined 18% mpg improvement,and still have easy access to your gear or cargo.

I know this is an old post, but I've been debating about how my vehicle fits into the above comment. I have an 09 Avalanche which has a factory sail panel, on the top it extends 8" on a slightly downward angle and at the bottom it is 30" with a larger inward taper. Also the factory tonneau removes in panels, there are 3 total (but the bed is only 5.25ft long). While I know I need to fill the holes in the sail panel in (I used plexiglass there on my older Avalanche), do you think this would be adequate or should the top be extended out at least the 20-24" that you mentioned to maximize the effect? (keeping in mind that it is a very short bed)

[freebeard]

What is it?

[aerohead]

Originally Posted by Jeff M

I know this is an old post, but I've been debating about how my vehicle fits into the above comment. I have an 09 Avalanche which has a factory sail panel, on the top it extends 8" on a slightly downward angle and at the bottom it is 30" with a larger inward taper. Also the factory tonneau removes in panels, there are 3 total (but the bed is only 5.25ft long). While I know I need to fill the holes in the sail panel in (I used plexiglass there on my older Avalanche), do you think this would be adequate or should the top be extended out at least the 20-24" that you mentioned to maximize the effect? (keeping in mind that it is a very short bed)

I'd have to speculate and I don't like to do that.
GM may have already optimized the Avalanche as a 'notchback'.
With the exception of converting to a K-form fastback roof line,she may already be as low as she will go as a notchback.
There's just so little info in the public domain.
You're at Cd 0.363.
GMC got to Cd 0.315 in the early 90s for Bonneville.It's at the bottom

[Jeff M]

I could never find the Cd for the newer model Avalanche, all I could find was the Tahoe or the original model. Thanks.

I guess when I get time one day I can make a frame up and pull one of my heavy canvas tarps over it and try a simulated aerocap for a week or two.

I wonder if removing the front section of my tonneau would make sense to try for now?

[freebeard]

A-B-A testing a half-tonneau would make a lot of sense.