Go Back   EcoModder Forum > EcoModding > Aerodynamics
Register Now
 Register Now

Reply  Post New Thread
Submit Tools LinkBack Thread Tools
Old 08-28-2017, 03:16 PM   #1 (permalink)
EcoModding Lurker
Join Date: Aug 2017
Location: State College Pa
Posts: 10
Thanks: 0
Thanked 7 Times in 4 Posts
New to Ecomodder; 1987 Econoline aero improvemnts

I've been gathering info off Ecomodder for some time now and have put some of the advice to use already. A friend and I purchased an 1987 Econoline E250 Club Wagon to use as a hunting rig to travel from PA to MT. The van had a 6.9 diesel with C6 automatic transmission and 4.10 gears. First thing swapped was the rearend, in with a 3.54 LS rear. Next we converted the transmission to a ZF5 manual transmission with transfer case(4x4 conversion at later date) Those conversions were done in 2015 and we took the van out to Montana that fall. Being new our mileage record keeping wasn't great but we averaged between 15-16 mpg hauling a 12' single axle trailer at speeds ranging from 70-80 mph.

In a short time the Banks Sidewinder turbo kit(used) installation will be complete. It was for an automatic transmission so we had to modify the up pipe to the turbo to clear the deeper bellhousing on the manual transmission. I'm hoping that will increase the efficiency of the engine and increase mileage.

I'm looking for feedback on my aerodynamic tail design that I am mocking up. I gathered up several aluminum truck caps to use as a shell and material. Amazing the width seemed to be nearly perfect, inside the rear body edge by about an inch on either side. I read that the angles should be about 15 degrees on the top and 10 degrees on the sides and bottom. The factory cap angle is about 12 degrees so honestly I rolled with that as the side angle. I have Coroplast to cover the shell and plan to attach the tail to the external door hinges on the back door. I know it's a bit rough now but looking for advice and or feedback to insure I'm doing ok.

This year we are not hauling a trailer, but plan on the same high speeds. Am I crazy to hope for 20mpg given the installation of the turbo and decent aero tail?

Thanks Jonathan

Attached Thumbnails
Click image for larger version

Name:	IMG_2701.jpg
Views:	217
Size:	100.6 KB
ID:	22542   Click image for larger version

Name:	IMG_2762.jpg
Views:	214
Size:	62.3 KB
ID:	22543   Click image for larger version

Name:	IMG_2768.jpg
Views:	216
Size:	52.0 KB
ID:	22544   Click image for larger version

Name:	IMG_2767.jpg
Views:	213
Size:	48.8 KB
ID:	22545   Click image for larger version

Name:	IMG_3728.jpg
Views:	215
Size:	46.6 KB
ID:	22546  

Click image for larger version

Name:	IMG_3730.jpg
Views:	220
Size:	42.6 KB
ID:	22547  
  Reply With Quote
The Following User Says Thank You to GillyF59 For This Useful Post:
aerohead (09-02-2017)
Alt Today
Popular topics

Other popular topics in this forum...

Old 08-28-2017, 03:51 PM   #2 (permalink)
Aero Wannabe
COcyclist's Avatar
Join Date: Dec 2007
Location: NW Colo
Posts: 551

TDi - '04 VW Golf
90 day: 55.96 mpg (US)
Thanks: 357
Thanked 113 Times in 91 Posts
Nice project. I hope you will post mileage as you test the tail. It reminds me of the trailer tails I am seeing on semi trucks these days.
60 mpg hwy highest, 55+mpg lifetime
TDi=fast frugal fun
make NOx not Carbon

"I worked on the wiring to see if I could get the alternator to charge. The stud was loose and I accidentally let the white smoke out of the box... Alternators, among other things, run on white smoke. Once you let the white smoke out they no longer work!" planejob
  Reply With Quote
Old 08-28-2017, 09:09 PM   #3 (permalink)
Cyborg ECU
California98Civic's Avatar
Join Date: Mar 2011
Location: Coastal Southern California
Posts: 4,889

Black and Green - '98 Honda Civic DX Coupe
Team Honda
90 day: 60.87 mpg (US)

Black and Red - '00 Nashbar Custom built eBike
90 day: 3671.43 mpg (US)
Thanks: 1,710
Thanked 1,394 Times in 955 Posts
In attaching to the door hinges are you making it possible for the tail to swing aside on demand for rear door access to the van?

The angles look good to me, but there are more expert eyes on this site. I will say, though, that the interaction between air coming up from under the van will be tricky and important. And the trnasitions from the sides and top should, I think, be closer to flush than you might have planned at the moment.

Also, side skirts on each side between the wheels, at the base of the van body... and rear wheel shirts.

See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.

  Reply With Quote
Old 08-28-2017, 10:23 PM   #4 (permalink)
EcoModding Lurker
Join Date: Aug 2017
Location: State College Pa
Posts: 10
Thanks: 0
Thanked 7 Times in 4 Posts
My hope for attachment and removal of the tail is that's it's easy. Travel the 1850 miles one way with the tail and remove it once we reach MT for the hunt and reinstall for the trip home. I agree about the transition on the bottom, I have plans to replace the factory bumper with a round tube bumper that should flow better and double as air tank if needed thou it will add a little weight but I think it's worth that. I forgot to mention that I did add a 6" air dam on the front that is lower than the lowest point under the chassis. Honestly one concern with side skirts would the strong crosswinds in the western states, could that blow us around on the highway at high speeds? Thanks. Jonathan
  Reply With Quote
Old 08-29-2017, 12:25 AM   #5 (permalink)
EcoModding flying lizard
Daschicken's Avatar
Join Date: May 2012
Location: Georgia
Posts: 527

Cibbie - '88 Honda CBR 250R
90 day: 53.94 mpg (US)

Rarity - '06 Honda Accord EX V6
Team Honda
90 day: 39.22 mpg (US)

Baby viff - '86 Honda VFR 400R
90 day: 48.31 mpg (US)
Thanks: 385
Thanked 160 Times in 108 Posts
Looks like you were already well on your path to ecomodding even before ecomodder! 20 mpg sounds like a perfectly reasonable goal, whether you will be able to do that towing a trailer at 70+ mph is another story.

It might be the angle of the pictures, but the top edge of the boat tail appears a little steep. Also, you are going to want to leave less of a "ramp" between the roof and the top of the boat tail. You don't want the air to skip your tail!
-Kaze o tatakaimasen-

Add yourself to the Ecomodder user map! As of 11/30/16 there are only 50 people on it!

132(Includes repeats...grr...) People as of 7/7/2018 Keep it up!


Best trip in v6: 52.0
Best tank in CBR: 60.5
Best tank in VFR: 55.3

Originally Posted by MetroMPG View Post
You can lead a fashion-conscious horse to unusual-looking water...

  Reply With Quote
Old 08-29-2017, 01:18 PM   #6 (permalink)
Master EcoModder
freebeard's Avatar
Join Date: Aug 2012
Location: northwest of normal
Posts: 11,177
Thanks: 2,536
Thanked 3,580 Times in 2,834 Posts
Thanks for asking and welcome to Ecomodder.
I'm looking for feedback on my aerodynamic tail design that I am mocking up. I gathered up several aluminum truck caps to use as a shell and material.
...and yet what I'm seeing is angle stock and sheeting. Is this:
  • a mockup template
  • the final product
I'm hoping the former. Can we see the 'several aluminum truck caps'?

I'm hoping the turbo helps because the mocked-up boat tail is more of a wake filler. Let's look at a proven design:

  • The sides and top are curved not flat.
  • The sides are flush.
  • The rear opening is [oval/squircular], not square.
This is not a boat tail, it is a boxed cavity.

What it shares with yours is the bottom is unfinished. Here is a car with a difusser to wrangle the underbody air flow. It is a divergent cavity with fences.

Side skirts aren't necessary, spats behind the front wheel and ahead of the rear wheel ala Morelli:

Are you planing a single piece that hangs on the hinges for easy removal, or split and hung on the doors? Two pieces might be easier to handle.

There exists on this site pictures of an aluminum box trailer with a split-gate full boat tail. Maybe someone knows where.
  Reply With Quote
Old 08-30-2017, 10:01 AM   #7 (permalink)
EcoModding Lurker
Join Date: Aug 2017
Location: State College Pa
Posts: 10
Thanks: 0
Thanked 7 Times in 4 Posts
Freebeard; Clearly this is a work in progress and my first attempt. Unfortunately I didn't not take pictures of the truck caps before dismantling them into usable pieces. I used the front and rear portions of the cap for the top and bottom. If I recall correctly one factory cap height was 42". All material used so far is 1" aluminum square tubing not angle stock.

Thank you for the picture you posted, I have seen it many times. That picture and Orbywan's thread on the AeroRV lead me here.

I have added so curved bows to the top section thou the curvature still isn't as much as your picture. Correct me if I'm wrong but haven't Class 8 trucks seen decent returns on their very linear designed tail.

My thoughts for the final tail/box cavity design is for it to have a 2" receiver mount that will slide into a hitch mount in a custom 4" tube bumper/air storage tank. The tail would suspended from a rack inside that would haul coolers and what not. I understand that sacrifices to a perfect design will have to made in order to have the tail easily removable for the hunting portion of the van's duty.

My assumption is that a fair attempt is better than no attempt. I realize it's not perfect but I'm having fun and I believe all Ecomodders have the same goal; Try to burn less fuel. I look forward to further discussions and feedback.

Thanks, Jonathan

Attached Thumbnails
Click image for larger version

Name:	IMG_3738.jpg
Views:	172
Size:	66.2 KB
ID:	22556   Click image for larger version

Name:	IMG_3739.jpg
Views:	175
Size:	53.0 KB
ID:	22557   Click image for larger version

Name:	IMG_3741.jpg
Views:	172
Size:	37.6 KB
ID:	22558   Click image for larger version

Name:	IMG_3742.jpg
Views:	174
Size:	22.3 KB
ID:	22559   Click image for larger version

Name:	IMG_3743.jpg
Views:	174
Size:	27.7 KB
ID:	22560  

  Reply With Quote
The Following 2 Users Say Thank You to GillyF59 For This Useful Post:
aerohead (09-02-2017), freebeard (08-31-2017)
Old 08-31-2017, 12:26 AM   #8 (permalink)
It's all about Diesel
cRiPpLe_rOoStEr's Avatar
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 6,688
Thanks: 0
Thanked 658 Times in 585 Posts
Thogh I'm not into extensive aeromods, I'm gonna keep an eye on this thread. BTW I see you're running a 6.9IDI Diesel, so, have you ever considered trying some alternate fuel? It's always good to remind that indirect-injection Diesels cope better with vegetable oils, for example, and sometimes they even get a better fuel-efficiency running on it instead of regular Diesel fuel.

But anyway, are you going to turn the aerodynamic tail into some useful extra load space?
  Reply With Quote
Old 08-31-2017, 01:04 AM   #9 (permalink)
EcoModding Lurker
Join Date: Aug 2017
Location: State College Pa
Posts: 10
Thanks: 0
Thanked 7 Times in 4 Posts
It Lives!!!!! Breathing new life with the turbo!!

And yes I would like to haul coolers and/or propane tanks for propane injection inside the tail.

Thanks for the advice on alternate fuels, we have talked about that a little bit but we really would only be able to use that on the first two tanks then we are too far from our home base. On a side note I did install a 38 gallon rear fuel tank plus the factory 21 gallon front tank, fill the filler necks and I think we can carry 60 gallons of fuel. Talk about range!!


  Reply With Quote
Old 08-31-2017, 01:06 AM   #10 (permalink)
EcoModding Lurker
Join Date: Aug 2017
Location: State College Pa
Posts: 10
Thanks: 0
Thanked 7 Times in 4 Posts
Darn I guess I can't post a video straight from the phone. I'll have too figure that out later.

  Reply With Quote
Reply  Post New Thread

Thread Tools

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2018, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com