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[GMCnet] 4.8 MPG [message #324190] Fri, 22 September 2017 09:59 Go to next message
glwgmc is currently offline  glwgmc   United States
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Interesting observation about finding better hill climbing ability running slightly richer, Justin. Maybe that is why I always felt the S and J engines in our Clasco and Royale made for wonderful driving machines for scampering around the west where mountains are a part of every trip. As I reported several times after returning from long adventures we rarely needed to downshift even on long grades yet I never allowed the engines to go to WOT (kept vacuum above 4") and didn't allow speed to drop below 45 mph.

Jerry Work
The Dovetail Joint
Fine furniture designed & hand crafted
in the 1907 former Masonic Temple building
in historic Kerby, OR
http://jerrywork.com


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Jerry & Sharon Work
78 Royale
Kerby, OR
Re: [GMCnet] 4.8 MPG [message #324193 is a reply to message #324190] Fri, 22 September 2017 10:51 Go to previous messageGo to next message
Justin Brady is currently offline  Justin Brady   United States
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Yep that's what I found.
I only had to downshift once after richening it up a bit and that was a crazy grade.
Mileage suffers a bit but totally worth it in the mountains imho


Justin Brady http://www.thegmcrv.com/ 1976 Palm Beach 455
Re: [GMCnet] 4.8 MPG [message #324208 is a reply to message #324193] Fri, 22 September 2017 13:31 Go to previous messageGo to next message
Gary Worobec is currently offline  Gary Worobec   United States
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I can;t recall who it is but some old sage on this list when asked how many mpg you should get with a GMC always answers “8 to 10 mpg”. Over the dozen or so years we have had our coach he is right on. No matter what you use, a carb or FI, what distributor you have, headers or no headers, a a 23 or a 26, towing or not towing it always is between “8 to 10”.


> On Sep 22, 2017, at 8:51 AM, Justin Brady wrote:
>
> Yep that's what I found.
> I only had to downshift once after richening it up a bit and that was a crazy grade.
> Mileage suffers a bit but totally worth it in the mountains imho
> --
> Justin Brady
> http://www.thegmcrv.com/
> 1976 Palm Beach 455
>
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> Unsubscribe or Change List Options:
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Gary Worobec
gtw5@earthlink.net
1973 23 GMC Glacier
Howell EFI/EBL




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Re: [GMCnet] 4.8 MPG [message #324212 is a reply to message #324208] Fri, 22 September 2017 14:18 Go to previous message
Jerry Wheeler is currently offline  Jerry Wheeler   United States
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Registered: January 2013
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The old sage said "8 to 10 depending on whether you tow or not". None
other than Gene Fisher...........
JR Wheeler 78 Royale NC/OR

On Fri, Sep 22, 2017 at 2:31 PM, Gary Worobec wrote:

> I can;t recall who it is but some old sage on this list when asked how
> many mpg you should get with a GMC always answers “8 to 10 mpg”. Over the
> dozen or so years we have had our coach he is right on. No matter what you
> use, a carb or FI, what distributor you have, headers or no headers, a a 23
> or a 26, towing or not towing it always is between “8 to 10”.
>
>
>> On Sep 22, 2017, at 8:51 AM, Justin Brady wrote:
>>
>> Yep that's what I found.
>> I only had to downshift once after richening it up a bit and that was a
> crazy grade.
>> Mileage suffers a bit but totally worth it in the mountains imho
>> --
>> Justin Brady
>> http://www.thegmcrv.com/
>> 1976 Palm Beach 455
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
> Gary Worobec
> gtw5@earthlink.net
> 1973 23 GMC Glacier
> Howell EFI/EBL
>
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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