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More Thoughts On A 21 Foot GMC [message #248948] Thu, 01 May 2014 15:15 Go to next message
A Hamilto is currently offline  A Hamilto   United States
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I imagined removing 24" from the middle of a 23' side bath, moving everything behind the door forward, cutting 2' out of the kitchen counter and leaving room for a 48" loveseat behind the driver's seat. Might even be able to keep the OEM stove and just replace the sink with a small bar unit.

http://www.gmcmhphotos.com/photos/data/4/medium/Floor_Plan_21_Foot.jpg
http://www.gmcmhphotos.com/photos/data/4/medium/Floor_Plan_21_Foot.jpg

I imagined redesigning the rear suspension to eliminate two wheels, leaving the original propane and generator compartments (and the water and waste tanks) intact.

http://www.gmcmhphotos.com/photos/data/1/medium/GMC_21_Foot_Profile.jpg
http://www.gmcmhphotos.com/photos/data/1/medium/GMC_21_Foot_Profile.jpg

One fuel tank would have to be customized to about 20 gallons instead of 25, or eliminated completely.

http://www.gmcmhphotos.com/photos/data/1/medium/GMC_21_Tanks.jpg
http://www.gmcmhphotos.com/photos/data/1/medium/GMC_21_Tanks.jpg

GVW would have to be less than 10,000 pounds (about 9,600), and care would have to be taken to keep from overloading either or both of the rear LRE tires. Voila! Toll charges the same as a passenger car and parking in a standard parking space.

[Updated on: Thu, 01 May 2014 15:15]

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Re: More Thoughts On A 21 Foot GMC [message #248949 is a reply to message #248948] Thu, 01 May 2014 16:12 Go to previous messageGo to next message
Harry is currently offline  Harry   Canada
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Would you have to cut the side with the door, go up and halfway across the roof cut lengthwise,to the back, then down the driver's side behind the window?
If you cut straight across, would you run in to the driver's side window?
Re: More Thoughts On A 21 Foot GMC [message #248954 is a reply to message #248949] Thu, 01 May 2014 17:50 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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Harry wrote on Thu, 01 May 2014 16:12

Would you have to cut the side with the door, go up and halfway across the roof cut lengthwise,to the back, then down the driver's side behind the window?
If you cut straight across, would you run in to the driver's side window?
On one like my 73's, I would take 24" out of the 60" window on the driver's side (replacing the window with a 36" one from a parts unit) and a 2' blank section out from behind the window that is behind the door. It would require a bit of lengthwise cutting. That would mean there would be a 30" window at the stove AND sink instead of just at the sink. Or could replace that 30" window with a 2' window out of a door. Lots of options.
Re: More Thoughts On A 21 Foot GMC [message #248962 is a reply to message #248948] Thu, 01 May 2014 19:56 Go to previous messageGo to next message
bwevers is currently offline  bwevers   United States
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Is 21 feet the legal limit for downtown parking?

Bill Wevers GMC49ers, GMC Western States 1975 Glenbrook - Manny Powerdrive, OneTon 455 F Block, G heads San Jose
Re: More Thoughts On A 21 Foot GMC [message #248965 is a reply to message #248962] Thu, 01 May 2014 20:25 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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bwevers wrote on Thu, 01 May 2014 19:56

Is 21 feet the legal limit for downtown parking?
Probably somewhere in North America. But not anywhere that I know of. My CanyonLands has a rusty frame behind the bogeys where it sat on the ground for quite a while before I acquired it. It is going to be a big job to replace the frame, and I was just daydreaming about taking the body off the frame and cutting off the last two (rusted) feet of frame. That led to the idea of removing 2' of body and the doodling is on the photo site.
Re: More Thoughts On A 21 Foot GMC [message #248966 is a reply to message #248965] Thu, 01 May 2014 20:29 Go to previous messageGo to next message
USAussie is currently offline  USAussie   Australia
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Mark, JimB has been there, done that: http://www.gmccoop.com/bobtail.htm


Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: More Thoughts On A 21 Foot GMC [message #248967 is a reply to message #248966] Thu, 01 May 2014 20:37 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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USAussie wrote on Thu, 01 May 2014 20:29

Mark, JimB has been there, done that: http://www.gmccoop.com/bobtail.htm
All he did on that one was cut off the back. Didn't leave room for a generator or propane tank. I think someone did one and eliminated one set of rear wheels, but don't know how long they left it or what they did with the interior.
Re: More Thoughts On A 21 Foot GMC [message #249137 is a reply to message #248967] Mon, 05 May 2014 20:50 Go to previous messageGo to next message
Byron Songer is currently offline  Byron Songer   United States
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Interesting. A Cortez in GMC skin. That rear end suspension would be similar to what Dunlop has found popular in Europe.


-- Byron Songer
Full-timing to enjoy the USA
Former owner but still an admirer
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Re: More Thoughts On A 21 Foot GMC [message #249138 is a reply to message #249137] Mon, 05 May 2014 21:02 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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Byron Songer wrote on Mon, 05 May 2014 20:50

Interesting. A Cortez in GMC skin. That rear end suspension would be similar to what Dunlop has found popular in Europe.

It is all just daydreaming. The rear suspension design could be something like half a quad bag system, or an OEM-like setup (with SullyBilt MarkBag) with the front swing arm bag connection attached solidly to the frame. I dunno. It was a slow day and I had time to dream, but I can't see myself ever having a place or the tools to do the work.
Re: More Thoughts On A 21 Foot GMC [message #249147 is a reply to message #248948] Tue, 06 May 2014 07:01 Go to previous messageGo to next message
Luvn737s is currently offline  Luvn737s   United States
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Put a driver's side door in and lower it so it fits in a garage and you'd have a winner (or a slick, stretched Vandura).

Randy
1973 26' Painted Desert
Ahwatukee (Phoenix) AZ
Re: More Thoughts On A 21 Foot GMC [message #249170 is a reply to message #249147] Tue, 06 May 2014 16:27 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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Luvn737s wrote on Tue, 06 May 2014 07:01

...lower it so it fits in a garage and you'd have a winner (or a slick, stretched Vandura).
That would involve removing everything from the roof and cutting headroom down at least a foot (since a "standard" garage door is 7' and a GMC is 8' tall).
Re: More Thoughts On A 21 Foot GMC [message #249171 is a reply to message #248948] Tue, 06 May 2014 16:45 Go to previous messageGo to next message
rcjordan   United States
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>Is 21 feet the legal limit for downtown parking?

About a year ago, someone here mentioned that 21' was the max for beach access parking in ??City??, California. Seems reasonable --well, reasonable for California.


SOLD 77 Royale Coachmen Side Dry Bath
76 Birchaven Coachmen Side Wet Bath
76 Eleganza
Elizabeth City, NC
Re: More Thoughts On A 21 Foot GMC [message #249297 is a reply to message #248948] Fri, 09 May 2014 23:07 Go to previous messageGo to next message
Chr$ is currently offline  Chr$   United States
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Just buy a vixen if you want garagability


-Chr$: Perpetual SmartAss
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Re: [GMCnet] More Thoughts On A 21 Foot GMC [message #249305 is a reply to message #249297] Sat, 10 May 2014 06:44 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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there was this one - 21 ft. gmc
http://www.gmcmhphotos.com/photos/tricked-out-gmcs/p1034.html
erf


On Fri, May 9, 2014 at 9:07 PM, Chris Choffat wrote:

> Just buy a vixen if you want garagability
>
> --
> -Chr$: Perpetual SmartAss
> Scottsdale, AZ
> 77 Ex-Kingsley Featuring: 455, Power Drive, 3:21, Rockwell, Jim B QJET,
> Qbag. Now for Sale
> 2010 Nomad 24 Ft Travel Trailer
>
> Photosite: Chrisc "It has Begun"
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Re: More Thoughts On A 21 Foot GMC [message #279010 is a reply to message #248948] Wed, 03 June 2015 13:18 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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Another slow day so I thought about other gains that could be realized by downsizing.

I am thinking a 2.73 final drive. AND maybe a smaller engine. Here's how:

Cut weight
-Remove 2 feet from body/frame ~ 900 pounds
-Remove mid wheels ~ 200 pounds
-Lightweight fittings and fixtures ~ 400(?) pounds
-Alloy wheels ~ 50 pounds
-Smaller engine ~ 100 pounds
Reduce drag
-Move roof AC inside under sofa
-More aerodynamic mirrors
-No roof storage pod
-No ladder or rails
Reduce rolling resistance
-Remove mid wheels

What else could be done to improve gas mileage?
Re: [GMCnet] More Thoughts On A 21 Foot GMC [message #279013 is a reply to message #279010] Wed, 03 June 2015 13:41 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Drive 45 mph. (GRIN)
Jim Hupy
Salem, Or.
78 GMC ROYALE 403
On Jun 3, 2015 11:18 AM, "A." wrote:

> Another slow day so I thought about other gains that could be realized by
> downsizing.
>
> I am thinking a 2.73 final drive. AND maybe a smaller engine. Here's how:
>
> Cut weight
> -Remove 2 feet from body/frame ~ 900 pounds
> -Remove mid wheels ~ 200 pounds
> -Lightweight fittings and fixtures ~ 400(?) pounds
> -Alloy wheels ~ 50 pounds
> -Smaller engine ~ 100 pounds
> Reduce drag
> -Move roof AC inside under sofa
> -More aerodynamic mirrors
> -No roof storage pod
> -No ladder or rails
> Reduce rolling resistance
> -Remove mid wheels
>
> What else could be done to improve gas mileage?
> --
> '73 23' Sequoia For Sale
> '73 23' CanyonLands For Sale
> Upper Alabama
> After all is said and done, a helluva lot more is said than done.
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Re: More Thoughts On A 21 Foot GMC [message #279031 is a reply to message #279010] Wed, 03 June 2015 20:17 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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A Hamilto wrote on Wed, 03 June 2015 13:18
...What else could be done to improve gas mileage?


At 21' with 4 wheels, you might as well put an interior in a GMC Vandura and get current fuel injection and OD tranny.


Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: More Thoughts On A 21 Foot GMC [message #279033 is a reply to message #248948] Wed, 03 June 2015 20:59 Go to previous messageGo to next message
Steve is currently offline  Steve   United States
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I find that I get much better mileage, and performance, when driving down hill.

1978 GMC Royal
Eastern Pennslyvania
1968 Chevrolet C20 396 Camper Special
1969 Chevrolet C20 Camper Special
1985 Buick Electra Park Avenue
1992 Camaro 25th Anniversary Heretage Edition Black
Re: More Thoughts On A 21 Foot GMC [message #279037 is a reply to message #279031] Wed, 03 June 2015 23:37 Go to previous message
A Hamilto is currently offline  A Hamilto   United States
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kerry pinkerton wrote on Wed, 03 June 2015 20:17
A Hamilto wrote on Wed, 03 June 2015 13:18
...What else could be done to improve gas mileage?
At 21' with 4 wheels, you might as well put an interior in a GMC Vandura and get current fuel injection and OD tranny.
But it wouldn't be traveling/camping in style...
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