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

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 05-21-2020, 12:23 AM   #81 (permalink)
Master EcoModder
 
aardvarcus's Avatar
 
Join Date: Apr 2012
Location: Evensville, TN
Posts: 676

Deep Blue - '94 GMC Suburban K2500 SLE
90 day: 23.75 mpg (US)

Griffin (T4R) - '99 Toyota 4Runner SR5
90 day: 25.43 mpg (US)
Thanks: 237
Thanked 580 Times in 322 Posts
Aerohead, thanks for all your feedback. I spent a bit of time crawling over the vehicle today with a tape measure. There is a bit more room than I had remembered at the start of the cargo area prior to the window to patch in some compound curve. Looks like at least 6 inches growing to 9. The cargo area is already tapered in with a minor amount of compound curve (.45 to .90 to 1.18 degrees) as you go back. I am contemplaing the angle to set the sides. Doing some overlays, i am considering aiming for 6 degrees right after the 6-9 inch transition. That results in the vechicle sloping from 76 inches down to approximately 60 inches over a lenght of 69 inches, pulled in 6.5 more inches per side from stock. This seems to reasonably align with a 4:1 streamline from a top view.

There really isnt a constraint on the angle i set provided it stays between 4.2 and 7.3 degrees, with rear widths between 64 and 57 inches for that range. Obviously this is a big project so I would like to squeeze out as much as possible.

  Reply With Quote
The Following User Says Thank You to aardvarcus For This Useful Post:
aerohead (05-22-2020)
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 05-22-2020, 12:27 PM   #82 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 15,892
Thanks: 23,969
Thanked 7,221 Times in 4,648 Posts
over a length

Quote:
Originally Posted by aardvarcus View Post
Aerohead, thanks for all your feedback. I spent a bit of time crawling over the vehicle today with a tape measure. There is a bit more room than I had remembered at the start of the cargo area prior to the window to patch in some compound curve. Looks like at least 6 inches growing to 9. The cargo area is already tapered in with a minor amount of compound curve (.45 to .90 to 1.18 degrees) as you go back. I am contemplaing the angle to set the sides. Doing some overlays, i am considering aiming for 6 degrees right after the 6-9 inch transition. That results in the vechicle sloping from 76 inches down to approximately 60 inches over a lenght of 69 inches, pulled in 6.5 more inches per side from stock. This seems to reasonably align with a 4:1 streamline from a top view.

There really isnt a constraint on the angle i set provided it stays between 4.2 and 7.3 degrees, with rear widths between 64 and 57 inches for that range. Obviously this is a big project so I would like to squeeze out as much as possible.
There's a plan-view image of Cybertruck online. Tesla gave it 6-different widths, kind of a planar approximation of body side camber. From the rear of the rear door cut line, Cybertruck is boat-tailed to the end of the vault. Very much like what you're going after on Deep Blue. A great mod!
__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/
  Reply With Quote
Old 07-19-2020, 02:09 PM   #83 (permalink)
Master EcoModder
 
aardvarcus's Avatar
 
Join Date: Apr 2012
Location: Evensville, TN
Posts: 676

Deep Blue - '94 GMC Suburban K2500 SLE
90 day: 23.75 mpg (US)

Griffin (T4R) - '99 Toyota 4Runner SR5
90 day: 25.43 mpg (US)
Thanks: 237
Thanked 580 Times in 322 Posts
A minor update, after stripping the interior and removing the fuel tank the angle grinder came out and removed the rear doors. No turning back now.

Same basic plan, narrow the rear leave the height the same. I am considering converting the rear to a lift up hatch. (E.g 3rd gen 4runner) Pictures to follow later, work to do now.
  Reply With Quote
The Following 2 Users Say Thank You to aardvarcus For This Useful Post:
aerohead (07-22-2020), freebeard (07-19-2020)
Old 07-20-2020, 08:20 AM   #84 (permalink)
Master EcoModder
 
aardvarcus's Avatar
 
Join Date: Apr 2012
Location: Evensville, TN
Posts: 676

Deep Blue - '94 GMC Suburban K2500 SLE
90 day: 23.75 mpg (US)

Griffin (T4R) - '99 Toyota 4Runner SR5
90 day: 25.43 mpg (US)
Thanks: 237
Thanked 580 Times in 322 Posts
Here are some pictures of yesterday's "progress." I carefully removed the metal near the front of where the taper starts because that area needs compound curved. I also started to do a few cuts on the inside where I know things need removed. Spend most of the time looking/planning more so than cutting at this point.
Attached Thumbnails
Click image for larger version

Name:	AA1.jpg
Views:	49
Size:	38.3 KB
ID:	28770   Click image for larger version

Name:	AA2.jpg
Views:	48
Size:	55.7 KB
ID:	28771  
  Reply With Quote
The Following 2 Users Say Thank You to aardvarcus For This Useful Post:
aerohead (07-22-2020), California98Civic (07-20-2020)
Old 07-20-2020, 10:35 AM   #85 (permalink)
Cyborg ECU
 
California98Civic's Avatar
 
Join Date: Mar 2011
Location: Coastal Southern California
Posts: 6,299

Black and Green - '98 Honda Civic DX Coupe
Team Honda
90 day: 66.42 mpg (US)

Black and Red - '00 Nashbar Custom built eBike
90 day: 3671.43 mpg (US)
Thanks: 2,373
Thanked 2,172 Times in 1,469 Posts
Quote:
Originally Posted by aardvarcus View Post
Here are some pictures of yesterday's "progress." I carefully removed the metal near the front of where the taper starts because that area needs compound curved. I also started to do a few cuts on the inside where I know things need removed. Spend most of the time looking/planning more so than cutting at this point.
Looking like commitment. I like it. How are you going to accomplish compound curves? Asking for a friend...

Quote:
Originally Posted by aardvarcus View Post
A minor update, after stripping the interior and removing the fuel tank the angle grinder came out and removed the rear doors. ...
"Minor"!

Nice to see an ambitious mod make progress. I agree with aerohead in an earlier post: you can with these somewhat harder edges get some significantly lower drag.

Subscribed.
__________________
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
The Following User Says Thank You to California98Civic For This Useful Post:
aardvarcus (07-20-2020)
Old 07-20-2020, 11:19 AM   #86 (permalink)
Master EcoModder
 
aardvarcus's Avatar
 
Join Date: Apr 2012
Location: Evensville, TN
Posts: 676

Deep Blue - '94 GMC Suburban K2500 SLE
90 day: 23.75 mpg (US)

Griffin (T4R) - '99 Toyota 4Runner SR5
90 day: 25.43 mpg (US)
Thanks: 237
Thanked 580 Times in 322 Posts
Compound curve will be accomplished via english wheel and planishing hammer. Note detailed sheet metal work is relatively new ground for me, I am not a bodywork expert, but with enough time and bondo anything is possible.
  Reply With Quote
The Following 2 Users Say Thank You to aardvarcus For This Useful Post:
aerohead (07-22-2020), California98Civic (07-20-2020)
Old 07-20-2020, 12:46 PM   #87 (permalink)
Cyborg ECU
 
California98Civic's Avatar
 
Join Date: Mar 2011
Location: Coastal Southern California
Posts: 6,299

Black and Green - '98 Honda Civic DX Coupe
Team Honda
90 day: 66.42 mpg (US)

Black and Red - '00 Nashbar Custom built eBike
90 day: 3671.43 mpg (US)
Thanks: 2,373
Thanked 2,172 Times in 1,469 Posts
Quote:
Originally Posted by aardvarcus View Post
Compound curve will be accomplished via english wheel and planishing hammer. Note detailed sheet metal work is relatively new ground for me, I am not a bodywork expert, but with enough time and bondo anything is possible.
Sounds great. Good clean compound curves, with smoothed welds and polished metal, are an amazing thing of beauty. I hope you'll share progress on that work. Will be fun to observe.
__________________
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
The Following User Says Thank You to California98Civic For This Useful Post:
aardvarcus (07-20-2020)
Old 07-22-2020, 10:27 AM   #88 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 15,892
Thanks: 23,969
Thanked 7,221 Times in 4,648 Posts
new ground

Quote:
Originally Posted by aardvarcus View Post
Compound curve will be accomplished via english wheel and planishing hammer. Note detailed sheet metal work is relatively new ground for me, I am not a bodywork expert, but with enough time and bondo anything is possible.
A copy of 'The Key to Metal Bumping', would be an indispensable companion if you don't already have a copy. Eastwood is a great source.
There are old-world metal-crafters in Europe that can make anything with a hardwood tree stump, hammers, mallets, dollies, spoons, and a leather shot-bag.
__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/
  Reply With Quote
The Following User Says Thank You to aerohead For This Useful Post:
aardvarcus (07-24-2020)
Old 07-22-2020, 02:58 PM   #89 (permalink)
Cyborg ECU
 
California98Civic's Avatar
 
Join Date: Mar 2011
Location: Coastal Southern California
Posts: 6,299

Black and Green - '98 Honda Civic DX Coupe
Team Honda
90 day: 66.42 mpg (US)

Black and Red - '00 Nashbar Custom built eBike
90 day: 3671.43 mpg (US)
Thanks: 2,373
Thanked 2,172 Times in 1,469 Posts
Quote:
Originally Posted by aerohead View Post
A copy of 'The Key to Metal Bumping', would be an indispensable companion if you don't already have a copy. Eastwood is a great source.
There are old-world metal-crafters in Europe that can make anything with a hardwood tree stump, hammers, mallets, dollies, spoons, and a leather shot-bag.
Edward De Vaucorbeil, a "French native metalshaper granted an extraordinary ability by the U.S. Gov.," is on Instagram with the handle extraordinary_metalshaping. Some examples of his most recent postings... pure beauty in craft...

Attached Thumbnails
Click image for larger version

Name:	20200722_115652.jpg
Views:	150
Size:	45.6 KB
ID:	28791  
__________________
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
The Following 2 Users Say Thank You to California98Civic For This Useful Post:
aardvarcus (07-24-2020), aerohead (07-22-2020)
Old 07-22-2020, 03:30 PM   #90 (permalink)
Master EcoModder
 
freebeard's Avatar
 
Join Date: Aug 2012
Location: northwest of normal
Posts: 27,690
Thanks: 7,774
Thanked 8,584 Times in 7,068 Posts
The final stages could borrow from paintless dent removal techniques — a glancing high-powered light and nylon pencil-pointed pecking hammers.

__________________
.
.
Without freedom of speech we wouldn't know who all the idiots are. -- anonymous poster

____________________
.
.
"We're deeply sorry." -- Pfizer
  Reply With Quote
The Following 2 Users Say Thank You to freebeard For This Useful Post:
aardvarcus (07-24-2020), aerohead (07-22-2020)
Reply  Post New Thread


Tags
suburban diesel 4x4 gmc





Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com