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

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 05-30-2008, 06:16 PM   #1 (permalink)
Legend in my own mind
 
trikkonceptz's Avatar
 
Join Date: Apr 2008
Location: Homestead, Fl.
Posts: 927

Evil Pumpkin - '08 Scion xD RS 1.0 #1633
90 day: 35.45 mpg (US)

Silent Silver Killer - '10 Honda Insight EX
90 day: 51.5 mpg (US)
Thanks: 2
Thanked 13 Times in 12 Posts
Vibe Kammback / Boat tail

I started this thread to not thread jack the CRX one but I too an heading down the road of heavy body modification. Not because its practical, but because I can.

My question though is;

Rather than building a full boat tail, what benefit / drawback will I see by building a proper Kammback and partial rea bumper boat tail?

Here is a profile pic of the Vibe, mind you it will go one of two ways;
-The way it is with a kammback and partial rear bumper boat tail
-Or sloped roofline with partial bumper boat tail.

Attached Thumbnails
Click image for larger version

Name:	VibeSide.JPG
Views:	93
Size:	41.0 KB
ID:	827  
__________________
Thx NoCO2; "The biggest FE mod you can make is to adjust the nut behind the wheel"

I am a precisional instrument of speed and aeromatics
If your knees bent in the opposite direction......what would a chair look like???





  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 05-30-2008, 07:19 PM   #2 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 8,367
Thanks: 10,260
Thanked 4,399 Times in 2,441 Posts
Vibe Kamm back / boat-tail

trikkonceptz, good question.And your in luck,as you already have the Kamm-back.GM and Toyota have done a really good job on the Matrix/Vibe aero and you should have clean,fully attached flow,up to where your Vibe ends.This was the whole point behind Kamm's work.And with the wagon-back body style you get to steer around C-pillar vortices which I must be careful about with my fastback.And even better for you,is that the body of the Vibe/Matrix begins plan-taper contraction quite a bit forward along it's length,adding pressure along the sides and also top,as the top is also carefully sloping downward as well. All of this means that you can have more aggressive sloping on the tail.So for you,the decision is,how long do you want to make it? If you merely follow the natural progression of the Vibes contours,you'll get a beautiful converging boat-tail and you can chop it off wherever you like ( truncating ).The further back you go,the steeper the slope can be.I posted a thread about the Gentoo Penguin with Cd 0.07 at GOOGLE Images,page 3,showing a single penguin swimming underwater.That's your boat-tail.And a parting thought,as this place is going to close down at 5:30. In the picture of the Mercedes-Benz C-111,they used 28-inches of boat-tail,and it dropped the Cd from 0.2378,to 0.195.Had Mercedes gone ahead and used the full length ( 60-inches ) the Cd would have dropped to 0.178 ( another 25 % drop! ) and the car would have beat it's own record.Consider some concession on length,as you've got to be able to park that thing,and you don't want to knock pedestrians over when you round a corner.If you want to go really crazy like me,consider a very light streamliner trailer for extended highway travel,that would plug into a receiver hitch.It could cut drag to bare minimum on the open road,then you could yank it for daily commuting.Compromise sucks but somehow reality has intruded into my imaginary drag-free world,and even I have had to make some compromises to survive in traffic.Keep us posted,good luck,Phil
__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/
  Reply With Quote
Old 05-30-2008, 07:23 PM   #3 (permalink)
Pokémoderator
 
cfg83's Avatar
 
Join Date: Dec 2007
Location: Southern California
Posts: 5,864

1999 Saturn SW2 - '99 Saturn SW2 Wagon
Team Saturn
90 day: 40.49 mpg (US)
Thanks: 439
Thanked 520 Times in 349 Posts
trikkonceptz -

I did this for fun (I am a Vibe fan) :



Don't know if it would work. Just looks cool to me.

CarloSW2
__________________

What's your EPA MPG? Go Here and find out!
American Solar Energy Society
  Reply With Quote
Old 05-30-2008, 07:49 PM   #4 (permalink)
Legend in my own mind
 
trikkonceptz's Avatar
 
Join Date: Apr 2008
Location: Homestead, Fl.
Posts: 927

Evil Pumpkin - '08 Scion xD RS 1.0 #1633
90 day: 35.45 mpg (US)

Silent Silver Killer - '10 Honda Insight EX
90 day: 51.5 mpg (US)
Thanks: 2
Thanked 13 Times in 12 Posts
^^^ Your pictures is exactly where I am heading within the next 60 days ...

But I wanted to start a partial boat tail also coming up from the bumper in order to extend the Kammback a little more .... HOWEVER ....

The idea of building a trailer to slip stream the rear is AWESOME !!! I can use it on my work commute daily 55 miles each way all hwy, and disconnect it for city driving where my speeds are always 40mph or less ...

Is that trailer theory theoretical or actual? Because otherwise I'm going to harbor frieght this weekend and buying a very light small utility trailer and getting to work .. LOL

Laterz ...
__________________
Thx NoCO2; "The biggest FE mod you can make is to adjust the nut behind the wheel"

I am a precisional instrument of speed and aeromatics
If your knees bent in the opposite direction......what would a chair look like???





  Reply With Quote
Old 05-30-2008, 11:37 PM   #5 (permalink)
Boxhead
 
whokilledthejams's Avatar
 
Join Date: May 2008
Location: Fredonia, NY
Posts: 322

Boxy Brown - '04 Scion xB
90 day: 35.48 mpg (US)
Thanks: 0
Thanked 1 Time in 1 Post
Send a message via AIM to whokilledthejams
@Aerohead--

Might I suggest finding/building a single-wheel trailer? They use two hitches, so it only pivots vertically, rather than horizontally. Hypothetically, one wouldn't need as much clearance as with a conventional trailer. I've looked into it myself, and it's something that I think would take more fabrication resources than I currently have at my disposal, but it's an option that I just don't think many people are aware of.

Here's a fairly informative site about vintage single wheelers: http://www.singlewheel.com/

Further googling comes up with several companies that make modern single wheel platform trailers that could be adapted with varying degrees of difficulty.

Still, it would probably be easiest to simply build a small one, perhaps similar to this teardrop: http://www.aircooledtech.com/single_wheel_trailer/

Needless to say, a small teardrop trailer appeals to me, because I'm too vain for a Kammback/boattail on a car I'm still paying for. Just my $.02, is all.
__________________
  Reply With Quote
Old 05-31-2008, 12:04 AM   #6 (permalink)
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 19,650

Blackfly - '98 Geo Metro
Team Metro
90 day: 70.72 mpg (US)

ForkenSwift - '92 Geo Metro EV
Last 3: 95.68 mpg (US)

MPGiata - '90 Mazda Miata
90 day: 47.99 mpg (US)
Thanks: 2,136
Thanked 4,894 Times in 2,459 Posts
The trailer idea isn't theoretical - aerohead built and tested a 1-wheel aerotrailer on his CRX.

Whokilledthejams - your Scion would be an ideal vehicle for a tapered trailer too. Welcome to the forum, by the way.
__________________
Latest mods test: 15 mods = 15% MPG improvement: A-B test, 2007 Honda Civic 1.8L, 5-speed
Ecodriving test:
Manual vs. automatic transmission MPG showdown: Nissan Micra 1.6L



EcoModder
has launched a forum for the efficient new Mitsubishi Mirage
www.MetroMPG.com - fuel efficiency info for Geo Metro owners
www.ForkenSwift.com - electric car conversion on a beer budget
  Reply With Quote
Old 05-31-2008, 12:13 AM   #7 (permalink)
Boxhead
 
whokilledthejams's Avatar
 
Join Date: May 2008
Location: Fredonia, NY
Posts: 322

Boxy Brown - '04 Scion xB
90 day: 35.48 mpg (US)
Thanks: 0
Thanked 1 Time in 1 Post
Send a message via AIM to whokilledthejams
Quote:
Originally Posted by MetroMPG View Post
The trailer idea isn't theoretical - aerohead built and tested a 1-wheel aerotrailer on his CRX.

Whokilledthejams - your Scion would be an ideal vehicle for a tapered trailer too. Welcome to the forum, by the way.
Thanks. I'm not the least bit surprised someone's built an aero single wheeler already, actually. It's definitely something for me to look into in the future (not that cargo capacity is an issue for me).
__________________
  Reply With Quote
Old 05-31-2008, 12:23 AM   #8 (permalink)
Legend in my own mind
 
trikkonceptz's Avatar
 
Join Date: Apr 2008
Location: Homestead, Fl.
Posts: 927

Evil Pumpkin - '08 Scion xD RS 1.0 #1633
90 day: 35.45 mpg (US)

Silent Silver Killer - '10 Honda Insight EX
90 day: 51.5 mpg (US)
Thanks: 2
Thanked 13 Times in 12 Posts
DAM .. the idea keeps getting better, and I do have the resources to get it done, even building one from scratch. If I can muster up some extra cash after my trip to tulsa next week I'll build it and I promise, once it works I will make it available to those vehicles I have access to (Scion xB's hint hint) for a very reasonable price, meaning costs, cuz this stuff is to fun ...
__________________
Thx NoCO2; "The biggest FE mod you can make is to adjust the nut behind the wheel"

I am a precisional instrument of speed and aeromatics
If your knees bent in the opposite direction......what would a chair look like???





  Reply With Quote
Old 01-19-2014, 02:57 AM   #9 (permalink)
EcoModding Lurker
 
Join Date: Dec 2013
Location: fremont,california,usa
Posts: 33

baby beluga - '90 toyota camry dx wagon
90 day: 29.21 mpg (US)

red1 - '97 Matsuda Miata
90 day: 31.01 mpg (US)
Thanks: 70
Thanked 2 Times in 2 Posts
So... WHUT HAPPEN?
__________________
Sorry, new users are not permitted to post links in their signatures.
  Reply With Quote
Old 01-19-2014, 10:59 AM   #10 (permalink)
Not banned yet
 
deejaaa's Avatar
 
Join Date: May 2010
Location: Baytown, Texas, close to Houston
Posts: 874

getto - '02 Volkswagen Jetta GLS TDI
90 day: 53.82 mpg (US)
Thanks: 405
Thanked 253 Times in 203 Posts
someone('s idea) died.

__________________
02 TDI Jetta- 5 sp: Cooper CS5 at 50 psi, UltraGauge, ventectomy, rear air shocks, mufflerectomy, LED plate light, upper fiberglass grille block, flat wheel covers, front/rear DVR, front lower pan, front fairing.
93 Chevy CrewCab 6.5 TurboDiesel, GearVendor OverDrive, 4L80 w/ full manual control. Now my DailyDriver


Quote:
Originally Posted by Daschicken View Post
....As of lately, I have started taking the bus to the other campus, because there are more people in space than there are parking spots over there.....
  Reply With Quote
Reply  Post New Thread


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Kammbacks & tail aero info Bearleener Aerodynamics 30 07-22-2010 07:56 PM
Rear Wheel Boat Tail Fabrication 2003protege Aerodynamics 1 07-24-2008 06:16 PM
Kammback design trikkonceptz Aerodynamics 1 05-07-2008 07:07 PM
Motor, battery and solar panels for a boat Wywern Fossil Fuel Free 11 02-17-2008 09:22 PM



Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com