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Finally fixed my main problem [message #100666] Wed, 22 September 2010 12:42 Go to next message
docsdad is currently offline  docsdad   United States
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Registered: May 2008
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Thanks to all who commented on my carb problems on my trip to Kansas. I stopped in IL at my son's home and ordered an aluminum manifold and EFI kit from Jim K. Installed per instructions, oops there are a few mistakes in the instructions, Read up on the various installs and finally with a few calls to Howell, got it installed and running. Note do not try to trouble shoot EFI with an empty gas tank. Don't ask me how I know. After all corrections made fired up and drove back to Georgia. The old GMC never had so much power and what a fun way to go. Had a little lean out when I got down in the 90+ degree heat of GA in late afternoon, but other than that ran like a dream. Went up Mt. Eagle mountain at 55 miles per hour. Could have gone faster but thats the speed limit and they patrol it heavily. I never had this kind of horse power before. Must have been either the manifold or the carb. But I don't care as it runs like it should now. I had planned to go to Dequoin, but family concerns required me to get back to GA. Maybe next year. Thanks to all and if you have questions on the installation, feel free to ask. I had to modify my throttle linkage and used a three wire oxygen sensor since I have headers. Had some problems with the vacum ports until I read up on previous installations and talked to Howell. Had to adjust timing twice to get rid of preignition but other than that it is an easy installation.

James Thompson 75 Avion GA
Re: Finally fixed my main problem [message #100668 is a reply to message #100666] Wed, 22 September 2010 12:56 Go to previous messageGo to next message
Keith V is currently offline  Keith V   United States
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
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Senior Member
Very encouraging, esp after some of the horror stories on here!

Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
Re: [GMCnet] Finally fixed my main problem [message #100669 is a reply to message #100666] Wed, 22 September 2010 13:05 Go to previous messageGo to next message
KRDietz is currently offline  KRDietz   United States
Messages: 133
Registered: July 2010
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Senior Member
It's amazing how getting the "12,000 hotrod with plumbing" truly
working makes you feel better about your GMC, huh? I used to hear
about it but actually experiencing it is pretty neat.

After 8 years I finally have that from '73 230. Used to hate seeing
hills. Now I can't wait. My wife is getting tired of me commenting
about how cool it is...

FWIW, you can get it with cast iron and a Quadrajet. Happy you found a
solution either way, though...

Kelvin

>
> Thanks to all who commented on my carb problems on my trip to Kansas. I stopped in IL at my son's home and ordered an aluminum manifold and EFI kit from Jim K. Installed per instructions, oops there are a few mistakes in the instructions, Read up on the various installs and finally with a few calls to Howell, got it installed and running. Note do not try to trouble shoot EFI with an empty gas tank. Don't ask me how I know. After all corrections made fired up and drove back to Georgia. The old GMC never had so much power and what a fun way to go. Had a little lean out when I got down in the 90+ degree heat of GA in late afternoon, but other than that ran like a dream. Went up Mt. Eagle mountain at 55 miles per hour. Could have gone faster but thats the speed limit and they patrol it heavily. I never had this kind of horse power before. Must have been either the manifold or the carb. But I don't care as it runs like it should now. I had planned to go to Dequoin,
b
> ut family concerns required me to get back to GA. Maybe next year. Thanks to all and if you have questions on the installation, feel free to ask. I had to modify my throttle linkage and used a three wire oxygen sensor since I have headers. Had some problems with the vacum ports until I read up on previous installations and talked to Howell. Had to adjust timing twice to get rid of preignition but other than that it is an easy installation.
>
> James Thompson 75 Avion GA
> _______________________________________________
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Re: [GMCnet] Finally fixed my main problem [message #100670 is a reply to message #100669] Wed, 22 September 2010 13:15 Go to previous messageGo to next message
docsdad is currently offline  docsdad   United States
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Registered: May 2008
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You are correct. My wife was about to have me get rid of it after our trip problems, but with the thing running as it does now, what a difference. When I pulled in at home, my son said what did you do, it sounds so much different and stronger. It is a joy to drive now. I passed semis going up the mountain and never felt any concern about getting out in the passing lane any more. Before it was always stay in the right lane so you can get over when it dies. Not any more.

James Thompson 75 Avion GA
Re: Finally fixed my main problem [message #100678 is a reply to message #100666] Wed, 22 September 2010 14:46 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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Registered: June 2008
Location: S. Ontario, Canada
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Senior Member
For me EFI made a big difference, but adding the EBL and an electronic spark controlled distributor made an even bigger difference!


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: Finally fixed my main problem [message #100688 is a reply to message #100678] Wed, 22 September 2010 15:48 Go to previous messageGo to next message
Neil is currently offline  Neil   United States
Messages: 271
Registered: July 2007
Location: Los Angeles and Magalia, ...
Karma: 1
Senior Member
snip "adding the EBL and an electronic spark controlled distributor made an even bigger difference"

forgive my ignorance, but what is "EBL"?


Neil
76 Eleganza now sold
Los Angeles
Re: [GMCnet] Finally fixed my main problem [message #100701 is a reply to message #100688] Wed, 22 September 2010 18:49 Go to previous messageGo to next message
ljdavick is currently offline  ljdavick   United States
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Location: Fremont, CA
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Senior Member
The EBL replaces the old processor with a more modern one and works
with great software to allow users to modify the parameters. And more.
Read all about it <http://www.dynamicefi.com>

Ljdavick at comcast.net

On Sep 22, 2010, at 1:48 PM, Neil Martin <nmartin@hfbllp.com> wrote:

>
>
> snip "adding the EBL and an electronic spark controlled distributor
> made an even bigger difference"
>
> forgive my ignorance, but what is "EBL"?
> --
> Neil
> 76 Eleganza
> Los Angeles
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Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy
Re: [GMCnet] Finally fixed my main problem [message #100709 is a reply to message #100701] Wed, 22 September 2010 19:52 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
For anyone interested in EFI, a reminder: We have a dedicated mailing list:
http://groups.google.com/group/gmcmh-efi?hl=en

Take a look and let me know if you want to join.


On 9/22/10, Larry Davick <ljdavick@comcast.net> wrote:
> The EBL replaces the old processor with a more modern one and works
> with great software to allow users to modify the parameters. And more.
> Read all about it <http://www.dynamicefi.com>
>
> Ljdavick at comcast.net
>
> On Sep 22, 2010, at 1:48 PM, Neil Martin <nmartin@hfbllp.com> wrote:
>
>>
>>
>> snip "adding the EBL and an electronic spark controlled distributor
>> made an even bigger difference"
>>
>> forgive my ignorance, but what is "EBL"?
>> --
>> Neil
>> 76 Eleganza
>> Los Angeles
>> _______________________________________________
>> GMCnet mailing list
>> List Information and Subscription Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>


--
Ken H.
Americus, GA
'76 X-Birchaven
www.gmcwipersetc.com
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Finally fixed my main problem [message #100806 is a reply to message #100668] Thu, 23 September 2010 13:31 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Location: Belmont, CA
Karma: 9
Senior Member
Kieth,
Let us know the flaw in the instructions so we can update or retained
consultants and update the kits we have in stock.
When the EFI runs well they are a dream (almost as good as the Moist ones)

On Wed, Sep 22, 2010 at 10:56 AM, Keith V <my427v8@hotmail.com> wrote:

>
>
> Very encouraging, esp after some of the horror stories on here!
> --
> Keith
> 69 Vette
> 29 Dodge
> 75 Royale GMC
> _______________________________________________
> GMCnet mailing list
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>



--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Finally fixed my main problem [message #100846 is a reply to message #100806] Fri, 24 September 2010 05:32 Go to previous messageGo to next message
docsdad is currently offline  docsdad   United States
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Registered: May 2008
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Member
Jim K

The instructions that I received with the kit still refer to using the rear vacumn port for the MAP sensor. This is wrong, Howell says to use the left front vacumn port for the MAP sensor and to use very short hose to MAP. Second the distributor should be connected to the ported vacumn which is the lower center front port. Instructions say front passenger side port which is manifold vacumn. I could not get rid of spark knock until I moved my distributor vac line to the center port.
The throttle bracket supplied will not fit on the aluminum manifold which has the large casting for port injection in the way. I would have had to machine off about 1/2 of the casting to make it fit and then my cruise control mounting would have had to be changed. I avoid this problem by using the original throttle bracket from carb, just making some small bracket extensions and mount off the adapter bolts. In addition the adapter has been changed so the throttle body does not set on top of the adapter holes, making it easier to install and does not cause my air cleaner to have to be modified (or my air cleaner is smaller than some) and my adapter leaves the mounting bolts free for the throttle mounting. It is a bit confusing however as the instructions say to fill the counterbore hole with RTV and there was no counterbore on my adapter plate My kit did not include any 1/4 inch fuel line for the return hose, but no big problem as this was available locally. For holding the air cleaner in place, I simply used the threaded rod from the carb, and shortened it a bit with a nut to hold the injectors in place and then used the wing nut to hold the top on the air cleaner.
But these minor things did not detract from the results. This conversion eliminated a major problem that I had with my coach and I would make the change again with out question. The results are excellent. I still have a few minor changes that I will make to improve my installation. I was in a hurry and need to clean up some wiring, plus my seat bracket is not stock and I had to mount the computer behind the passenger seat as a result, so I have to do some finish work there.
It is a great kit and I would recommend to all. If I had been aware of the computer controlled distributor, I would have added that also but now must wait until income tax time to save for my next purchase. My coach starts now, runs like it is supposed to and stops when the key turns off, no dieseling. Great improvement. I may have been able to do this with a proper carb, but by using the aluminum manifold. I got rid of the heat from exhaust problem, got rid of the EGR valve that was on my manifold eliminated the choke piping and have an engine that can climb hills with out a problem. Thanks for having this kit available.

James Thompson 75 Avion GA
Re: [GMCnet] Finally fixed my main problem [message #100848 is a reply to message #100806] Fri, 24 September 2010 07:17 Go to previous message
Keith V is currently offline  Keith V   United States
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
Karma: 0
Senior Member
jimk wrote on Thu, 23 September 2010 13:31

Kieth,
Let us know the flaw in the instructions so we can update or retained
consultants and update the kits we have in stock.
When the EFI runs well they are a dream (almost as good as the Moist ones)

On Wed, Sep 22, 2010 at 10:56 AM, Keith V <my427v8@hotmail.com> wrote:

>
>
> Very encouraging, esp after some of the horror stories on here!
> --
> Keith
> 69 Vette
> 29 Dodge
> 75 Royale GMC




Jim,
I don't have EFI and probably won't be getting one soon.
I have a WB O2 and am getting pretty good results with it and the carb.
Many things to fix before EFI comes to the top of the todo list


Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
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