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Re: [GMCnet] EFI vs Carb [message #326033] Wed, 15 November 2017 14:38 Go to next message
Ronald Pottol is currently offline  Ronald Pottol   United States
Messages: 505
Registered: September 2012
Location: Redwood City, California
Karma: -2
Senior Member
Where do you go? Up in the mountains to 10,000 feet or more? In freezing
temperatures? These extremes lean towards EFI.

On Nov 15, 2017 12:33, "Mike" wrote:

Hello All,

I'm considering an EFI system over a carb re-build, I would like some "real
world" experience, practical vs theory.

I can have my Rochester Quadrajet re-built or I can install an EFI system,
why one over the other and if EFI which system to go with?

I have read a bit about the Fitech Go Street and the Go EFI, is there a
major difference between the two (if you chose one over the other) and why,
or is there a brand which works better with our GMC's?

As always thank you for your feedback,
Regards,
Mike


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1973 26' GM outfitted
Re: [GMCnet] EFI vs Carb [message #326036 is a reply to message #326033] Wed, 15 November 2017 14:53 Go to previous messageGo to next message
bdub is currently offline  bdub   United States
Messages: 1578
Registered: February 2004
Location: Central Texas
Karma: 5
Senior Member

I understand that the MSD Atomic is CARB approved for use in CA. Miguel
Mendez swears by these.
https://www.msdperformance.com/brands/atomic/

bdub

On Wed, Nov 15, 2017 at 2:38 PM, Ronald Pottol
wrote:

> Where do you go? Up in the mountains to 10,000 feet or more? In freezing
> temperatures? These extremes lean towards EFI.
>
> On Nov 15, 2017 12:33, "Mike" wrote:
>
> Hello All,
>
> I'm considering an EFI system over a carb re-build, I would like some "real
> world" experience, practical vs theory.
>
> I can have my Rochester Quadrajet re-built or I can install an EFI system,
> why one over the other and if EFI which system to go with?
>
> I have read a bit about the Fitech Go Street and the Go EFI, is there a
> major difference between the two (if you chose one over the other) and why,
> or is there a brand which works better with our GMC's?
>
> As always thank you for your feedback,
> Regards,
> Mike
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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bdub
'76 Palm Beach/Central Texas
www.bdub.net
www.gmcmhphotos.com
www.gmcmotorhomemarketplace.com
www.gmcmhregistry.com
www.facebook.com/groups/classicgmcmotorhomes
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Re: [GMCnet] EFI vs Carb [message #326038 is a reply to message #326033] Wed, 15 November 2017 15:13 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
Senior Member
I currently swear >at< mine (Properly installed by Miguel) but I am coming to the conclusion that my lack of mileage is elsewhere in the drive line.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: [GMCnet] EFI vs Carb [message #326039 is a reply to message #326036] Wed, 15 November 2017 15:12 Go to previous messageGo to next message
Gary Worobec is currently offline  Gary Worobec   United States
Messages: 867
Registered: May 2005
Karma: -1
Senior Member


MSD says CARB approved for "use on 1987 and older GM passenger cars and trucks” which is great however I would check with a BAR referee to make sure that includes the GMC motorhome before I bought and installed it.









On Nov 15, 2017, at 12:53 PM,





Billy Massey wrote:
>
> I understand that the MSD Atomic is CARB approved for use in CA. Miguel
> Mendez swears by these.
> https://www.msdperformance.com/brands/atomic/
>
> bdub
>
> On Wed, Nov 15, 2017 at 2:38 PM, Ronald Pottol
> wrote:
>
>> Where do you go? Up in the mountains to 10,000 feet or more? In freezing
>> temperatures? These extremes lean towards EFI.
>>
>> On Nov 15, 2017 12:33, "Mike" wrote:
>>
>> Hello All,
>>
>> I'm considering an EFI system over a carb re-build, I would like some "real
>> world" experience, practical vs theory.
>>
>> I can have my Rochester Quadrajet re-built or I can install an EFI system,
>> why one over the other and if EFI which system to go with?
>>
>> I have read a bit about the Fitech Go Street and the Go EFI, is there a
>> major difference between the two (if you chose one over the other) and why,
>> or is there a brand which works better with our GMC's?
>>
>> As always thank you for your feedback,
>> Regards,
>> Mike
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
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>>
> _______________________________________________
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Gary Worobec
gtw5@earthlink.net
1973 23 GMC Glacier
1935 Dodge pickup






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Re: [GMCnet] EFI vs Carb [message #326041 is a reply to message #326033] Wed, 15 November 2017 16:46 Go to previous messageGo to next message
Larry is currently offline  Larry   United States
Messages: 2875
Registered: January 2004
Location: Menomonie, WI
Karma: 10
Senior Member
See this:

http://gmc.mybirdfeeder.net/GMCforum/index.php?t=msg&th=40012&start=0&rid=19

second comment in the thread.


Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: [GMCnet] EFI vs Carb [message #326042 is a reply to message #326033] Wed, 15 November 2017 17:48 Go to previous messageGo to next message
Adrien G. is currently offline  Adrien G.   United States
Messages: 474
Registered: May 2008
Location: Burns Flat, OK 73624
Karma: 1
Senior Member
Ron,

Don't worry about the smog, '73 to '75 are exempt from it ( '76 and later are still in the smog law), so change it to what you want.
These older vehicle where supposed to be dropped from the smog law, but greedy Kalifornia can't give up the $$$$...


Ronald Pottol wrote on Wed, 15 November 2017 12:38
Where do you go? Up in the mountains to 10,000 feet or more? In freezing
temperatures? These extremes lean towards EFI.

On Nov 15, 2017 12:33, "Mike" wrote:

Hello All,

I'm considering an EFI system over a carb re-build, I would like some "real
world" experience, practical vs theory.

I can have my Rochester Quadrajet re-built or I can install an EFI system,
why one over the other and if EFI which system to go with?

I have read a bit about the Fitech Go Street and the Go EFI, is there a
major difference between the two (if you chose one over the other) and why,
or is there a brand which works better with our GMC's?

As always thank you for your feedback,
Regards,
Mike


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Adrien & Jenny Genesoto 75 Glenbrook (26-3) Mods LS3.70 FD / Reaction Sys / 80mm Front&Intermidiate / Hydroboost / 16" Tires / Frame Rebuild / Interior Rebuild Yuba City,Ca. Text 530-nine-3-three-3-nine-nine-6
Re: [GMCnet] EFI vs Carb [message #326046 is a reply to message #326042] Wed, 15 November 2017 19:49 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
Mike,
I have grown up with EFI from 1990 and know the difference between the
Fitech,MSD,Holly,etc. vs the Howell based unit with the EBL Flash drive ECM.
Why do people not get the economy from these units?
It is all about Ignition timing control and program.The EBL has so much
computing inside the ECM that the others cannot hold a candle to it.
Also there are over 200-300 GMC owners that are running the EBL system.
There are lot of people running the basic Howell system without the EBL
option and not understanding the system.
We sell ALL the EFI units, but only the EBL system deliver the economy that
people are seeking . I can tell you that most of the people with the EBL
are getting minimum of 1-2 mpg economy.
It is a plug and play unit and we have few owners that know lot about it
should one develop problems.
Contact me should you have questions.
If you think for a second that by going to a EFI, you get around the vapor
lock problem, you do not understand fuel delivery.

On Wed, Nov 15, 2017 at 3:48 PM, Adrien Genesoto via Gmclist <
gmclist@list.gmcnet.org> wrote:

> Ron,
>
> Don't worry about the smog, '73 to '75 are exempt from it ( '76 and later
> are still in the smog law), so change it to what you want.
> These older vehicle where supposed to be dropped from the smog law, but
> greedy Kalifornia can't give up the $$$$...
>
>
> Ronald Pottol wrote on Wed, 15 November 2017 12:38
>> Where do you go? Up in the mountains to 10,000 feet or more? In freezing
>> temperatures? These extremes lean towards EFI.
>>
>> On Nov 15, 2017 12:33, "Mike" wrote:
>>
>> Hello All,
>>
>> I'm considering an EFI system over a carb re-build, I would like some
> "real
>> world" experience, practical vs theory.
>>
>> I can have my Rochester Quadrajet re-built or I can install an EFI
> system,
>> why one over the other and if EFI which system to go with?
>>
>> I have read a bit about the Fitech Go Street and the Go EFI, is there a
>> major difference between the two (if you chose one over the other) and
> why,
>> or is there a brand which works better with our GMC's?
>>
>> As always thank you for your feedback,
>> Regards,
>> Mike
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> --
> ”When we avoid the mistakes we might have made, we sometimes make the
> mistakes that we might have avoided.”
>
>
>
> Adrien & Jenny Genesoto
> 75 Glenbrook 26-3
> Yuba City,Ca. Text 530-nine-3-three-3-nine-nine-6
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>



--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
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jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] EFI vs Carb [message #326048 is a reply to message #326033] Wed, 15 November 2017 20:21 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
Senior Member
Jim - how's to expand on this a bit:

"If you think for a second that by going to a EFI, you get around the vapor
lock problem, you do not understand fuel delivery."

thanks,

Johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: [GMCnet] EFI vs Carb [message #326053 is a reply to message #326033] Wed, 15 November 2017 21:02 Go to previous messageGo to next message
GMC Jimmy is currently offline  GMC Jimmy   Canada
Messages: 199
Registered: September 2016
Location: Niagara, Ontario
Karma: 2
Senior Member
Thanks Jim and to the others that responded, I guess I'm just as confused by the decision to go with EFI over a properly tuned carb and which system to go with (if I decide to go with fuel injection), as many others are.

My issue began while on a trip to northern Ontario a couple of months ago. 1975 26' Royale by Coachmen,I left and the coach was running fine, temperature was around 75 degrees. A couple of hours into my drive I decided to stop for fuel, when I pulled into the service center the coach began running rough, idle was off and for the first time the coach stalled. After fuelling up it started fine but was clearly not running smooth, once on the highway it appeared to be running fine until I stopped again.

I let it cool down and after a few hours I fired it up and same issue. Next day same thing. Once I arrived home I noticed that the black soot left from the tail pipe suggested it was running rich. Replaced plugs, gapped at 54, wires, cap and rotor along with new air filter and fuel filters and it started and ran beautifully for a short run of ten minutes, then it started running rough again.

Replaced the coil and ignition module, installed a fresh set of plugs with a gap of 60, set the timing, fired right up and idled smooth for a few minutes then started acting up again, almost as though when getting to temp caused the idle issue. At this stage decided to do a compression check, everything was excellent except number 2 had ZERO compression, determined to be exhaust valve, seat jumped out.

Now I'm ready to have the heads and intake reinstalled after a valve job with everything new and carb cleaned out, at this stage trying to decide which way to go regarding EFI. I will do some research on the EBL system and will get in touch with Dick Paterson.

I would like to drive the coach out to California in the spring and obviously hoping for a reliable set up. Any additional opinions are welcome especially those which are based on experience with a particular system.

All the best,
Mike
Re: [GMCnet] EFI vs Carb [message #326054 is a reply to message #326053] Wed, 15 November 2017 21:42 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
Mike,

Your valve seat failure was undoubtedly the source of your problems.
Without knowing the history of the engine, I won't speculate on the cause
of that, 'tho' obviously the head had been rebuilt, and probably by someone
who didn't realize that the seats in the head were hardened from the
factory, so shouldn't have needed seats.

An alternate possibility for the symptoms you described is that the exhaust
crossover in the intake manifold has not been blocked. Without that mod,
vapor lock is MUCH more common with today's gasoline formulations. When
you talk to Dick Paterson, talk to him about that: He sells blockoff
plates and gaskets modified to work with them.

Finally, 0.054" or 0.060" gaps are too wide for the 455, despite the 0.080"
specified in the factory manuals. I think Dick will tell you to use
0.038". Wider gaps stress the ignition module (and other ignition
components) too severely.

Ken H.


On Wed, Nov 15, 2017 at 10:02 PM, Mike wrote:

> Thanks Jim and to the others that responded, I guess I'm just as confused
> by the decision to go with EFI over a properly tuned carb and which system
> to go with (if I decide to go with fuel injection), as many others are.
>
> My issue began while on a trip to northern Ontario a couple of months ago.
> 1975 26' Royale by Coachmen,I left and the coach was running fine,
> temperature was around 75 degrees. A couple of hours into my drive I
> decided to stop for fuel, when I pulled into the service center the coach
> began
> running rough, idle was off and for the first time the coach stalled.
> After fuelling up it started fine but was clearly not running smooth, once
> on
> the highway it appeared to be running fine until I stopped again.
>
> I let it cool down and after a few hours I fired it up and same issue.
> Next day same thing. Once I arrived home I noticed that the black soot left
> from the tail pipe suggested it was running rich. Replaced plugs, gapped
> at 54, wires, cap and rotor along with new air filter and fuel filters and
> it
> started and ran beautifully for a short run of ten minutes, then it
> started running rough again.
>
> Replaced the coil and ignition module, installed a fresh set of plugs with
> a gap of 60, set the timing, fired right up and idled smooth for a few
> minutes then started acting up again, almost as though when getting to
> temp caused the idle issue. At this stage decided to do a compression check,
> everything was excellent except number 2 had ZERO compression, determined
> to be exhaust valve, seat jumped out.
>
> Now I'm ready to have the heads and intake reinstalled after a valve job
> with everything new and carb cleaned out, at this stage trying to decide
> which way to go regarding EFI. I will do some research on the EBL system
> and will get in touch with Dick Paterson.
>
> I would like to drive the coach out to California in the spring and
> obviously hoping for a reliable set up. Any additional opinions are welcome
> especially those which are based on experience with a particular system.
>
> All the best,
> Mike
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] EFI vs Carb [message #326056 is a reply to message #326054] Wed, 15 November 2017 22:45 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
Johnny,
Vapor lock phenomenon develops any where between the tank and the
carburetor / throttle body.
Should one not address that, you will run into this issue at one time or
another.
I'll address it later as I have several things that need to be addressed
now.

On Wed, Nov 15, 2017 at 7:42 PM, Ken Henderson
wrote:

> Mike,
>
> Your valve seat failure was undoubtedly the source of your problems.
> Without knowing the history of the engine, I won't speculate on the cause
> of that, 'tho' obviously the head had been rebuilt, and probably by someone
> who didn't realize that the seats in the head were hardened from the
> factory, so shouldn't have needed seats.
>
> An alternate possibility for the symptoms you described is that the exhaust
> crossover in the intake manifold has not been blocked. Without that mod,
> vapor lock is MUCH more common with today's gasoline formulations. When
> you talk to Dick Paterson, talk to him about that: He sells blockoff
> plates and gaskets modified to work with them.
>
> Finally, 0.054" or 0.060" gaps are too wide for the 455, despite the 0.080"
> specified in the factory manuals. I think Dick will tell you to use
> 0.038". Wider gaps stress the ignition module (and other ignition
> components) too severely.
>
> Ken H.
>
>
> On Wed, Nov 15, 2017 at 10:02 PM, Mike wrote:
>
>> Thanks Jim and to the others that responded, I guess I'm just as confused
>> by the decision to go with EFI over a properly tuned carb and which
> system
>> to go with (if I decide to go with fuel injection), as many others are.
>>
>> My issue began while on a trip to northern Ontario a couple of months
> ago.
>> 1975 26' Royale by Coachmen,I left and the coach was running fine,
>> temperature was around 75 degrees. A couple of hours into my drive I
>> decided to stop for fuel, when I pulled into the service center the coach
>> began
>> running rough, idle was off and for the first time the coach stalled.
>> After fuelling up it started fine but was clearly not running smooth,
> once
>> on
>> the highway it appeared to be running fine until I stopped again.
>>
>> I let it cool down and after a few hours I fired it up and same issue.
>> Next day same thing. Once I arrived home I noticed that the black soot
> left
>> from the tail pipe suggested it was running rich. Replaced plugs, gapped
>> at 54, wires, cap and rotor along with new air filter and fuel filters
> and
>> it
>> started and ran beautifully for a short run of ten minutes, then it
>> started running rough again.
>>
>> Replaced the coil and ignition module, installed a fresh set of plugs
> with
>> a gap of 60, set the timing, fired right up and idled smooth for a few
>> minutes then started acting up again, almost as though when getting to
>> temp caused the idle issue. At this stage decided to do a compression
> check,
>> everything was excellent except number 2 had ZERO compression, determined
>> to be exhaust valve, seat jumped out.
>>
>> Now I'm ready to have the heads and intake reinstalled after a valve job
>> with everything new and carb cleaned out, at this stage trying to decide
>> which way to go regarding EFI. I will do some research on the EBL system
>> and will get in touch with Dick Paterson.
>>
>> I would like to drive the coach out to California in the spring and
>> obviously hoping for a reliable set up. Any additional opinions are
> welcome
>> especially those which are based on experience with a particular system.
>>
>> All the best,
>> Mike
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>



--
Jim Kanomata
Applied/GMC, Newark,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] EFI vs Carb [message #326071 is a reply to message #326033] Thu, 16 November 2017 11:01 Go to previous messageGo to next message
GMC Jimmy is currently offline  GMC Jimmy   Canada
Messages: 199
Registered: September 2016
Location: Niagara, Ontario
Karma: 2
Senior Member
Ken, apparently my motor had been rebuilt by the PO, unfortunately I do not have any documentation to support this. I was told by the fellow assisting me with this issue that the engine as far as he could tell looks like it had undergone some level of rebuild not that long ago due to the condition and cleanliness of the heads and intake once they were removed.

We also found the exhaust block-off plates on the intake manifold tray. I never experienced vapor lock issues although I never really put that many miles on the coach this summer.

I will discuss with Dick Paterson the carb rebuild and distributor service before making a final call on the EFI decision.

Also noted on the spark plug gap, I did a bit of research on this and the suggestions varied from 40 to 80, I'll know better next time, I plan on a fresh set of plugs before final start-up.

Thanks again,
Mike
Re: [GMCnet] EFI vs Carb [message #326076 is a reply to message #326071] Thu, 16 November 2017 12:36 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
The gap should be .040 as athig more puts too much load on the system. Once
a spec is entered, it is hard to delete.
If you do not believe us, then go .080 and suffer later.

On Thu, Nov 16, 2017 at 9:01 AM, Mike wrote:

> Ken, apparently my motor had been rebuilt by the PO, unfortunately I do
> not have any documentation to support this. I was told by the fellow
> assisting
> me with this issue that the engine as far as he could tell looks like it
> had undergone some level of rebuild not that long ago due to the condition
> and cleanliness of the heads and intake once they were removed.
>
> We also found the exhaust block-off plates on the intake manifold tray. I
> never experienced vapor lock issues although I never really put that many
> miles on the coach this summer.
>
> I will discuss with Dick Paterson the carb rebuild and distributor service
> before making a final call on the EFI decision.
>
> Also noted on the spark plug gap, I did a bit of research on this and the
> suggestions varied from 40 to 80, I'll know better next time, I plan on a
> fresh set of plugs before final start-up.
>
> Thanks again,
> Mike
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>



--
Jim Kanomata
Applied/GMC, Newark,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
UPDATE Re: [GMCnet] EFI vs Carb [message #326441 is a reply to message #326033] Tue, 28 November 2017 12:03 Go to previous messageGo to next message
GMC Jimmy is currently offline  GMC Jimmy   Canada
Messages: 199
Registered: September 2016
Location: Niagara, Ontario
Karma: 2
Senior Member
UPDATE... still on the proverbial fence.
Considered EFI, asked on the forum about opinions for and against. Received several opinions and decided that before I made my final decision I would speak with Dick Paterson.

Excellent conversation with Dick lead me to lean heavily in favor of Carb rebuild with distributor re-curve etc. Then after doing more research and talking with a few others that have experience with EFI systems I decided to order the Fitech Go Street EFI with the FCC (fuel command center).

After reading a blog from a member of this forum regarding his install of the Fitech EFI (I read it after I ordered and received my EFI) I began to question the need for the FCC as I was hoping for possible relief from vapor-lock as well as peace of mind & efficiency.

Decided I would move forward with the EFI but not include the FCC in my install and go with a new mechanical fuel pump with the return port, which I do not have on my current pump. My thinking, along with the assistance of a friend who is assisting me with this project, was that I could do a few more things to reduce vapor-lock issues by wrapping heat shielding sleeve around my fuel lines and fuel filter and run some new hard fuel lines away from exposure to areas of direct heat where possible.

Then when testing the fitment of the new EFI throttle body and the existing air breather it became evident that I would need to make some adjustments to make everything fit comfortably under the hatch. (I do not want to raise the hatch above the floor line)

As a side note, when you read that these systems are a direct fit - bolt on system, the system might fit but the accessories you require will probably need modification. This system requires a fair bit of playing with and adjusting to make things fit properly.

When it became obvious that I would not be able to make the throttle body and existing air breather assembly fit without modifying the hatch and the assembly due to the fixed fuel return port on the EFI, I decided to re-consider the carb once again.

Thinking this challenge through raised the option of a cold-air intake system with a ultra low profile air plenum / carb hat. This would allow for the EFI to mount on the intake while providing air from a cone style filter on the end of a snorkel positioned down in a area which will receive good air flow, while not interfering with the floor hatch.

I can design and weld up a custom low profile air plenum which will fit but do I require a specific amount of space in the air plenum to make this all work, CFM?

Will I need an MAF sensor? (I'm not sure if the Fitech has one built-in)

Has anyone else experienced this and which air filter did you use?

As always thanks for your experience and suggestions,

Regards,
Mike

[Updated on: Tue, 28 November 2017 18:41]

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Re: [GMCnet] EFI vs Carb [message #326442 is a reply to message #326033] Tue, 28 November 2017 13:17 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
Messages: 2324
Registered: October 2010
Location: St. Cloud, MN
Karma: 5
Senior Member
You need to do some more research as many have easily installed without raising the hatch. It does require normally a remote air filter. I think applied has some varients that should be complete kits.

No need for maf sensor, just need to get filtered air to the fi-tech.

Fuel delivery is the wild card as there are people happy with the fcc, and others have experienced issues.

Call those that have some miles on there setup. Lots of work, but i think the best way is to get in-tank pumps. I do not hear of problems with people get in-tank pumps. Sure the pump can die, but all pumps can die.


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: [GMCnet] UPDATE Re: EFI vs Carb [message #326443 is a reply to message #326441] Tue, 28 November 2017 14:25 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
Messages: 7117
Registered: August 2005
Karma: 2
Senior Member
On Tue, Nov 28, 2017 at 10:10 AM Mike wrote:

> UPDATE... still on the proverbial fence.


Makes me wonder also
I have 3 gmc
2 w howel one Atomic
So why did our big guns sell all their gmc less than a year after they went
fi ??? (Work and Minnie )
I just dunno

>
> Considered EFI, asked on the forum about opinions for and against.
> Received several opinions and decided that before I made my final decision
> I would
> speak with Dick Paterson.
>
> Excellent conversation with Dick lead me to lean heavily in favor of Carb
> rebuild with distributor re-curve etc. Then after doing more research and
> talking with a few others that have experience with EFI systems I decided
> to order the Fitech Go Street EFI with the FCC (fuel command center).
>
> After reading a blog from a member of this forum regarding his install of
> the Fitech EFI (I read it after I ordered and received my EFI) I began to
> question the need for the FCC as I was hoping for possible relief from
> vapor-lock as well as peace of mind & efficiency.
>
> Decided I would move forward with the EFI but not include the FCC in my
> install and go with a new mechanical fuel pump with the return port, which I
> do not have on my current pump. My thinking, along with the assistance of
> a friend who is assisting me with this project, was that I could do a few
> more things to reduce vapor-lock issues by wrapping heat shielding sleeve
> around my fuel lines and fuel filter and run some new hard fuel lines away
> from exposure to areas of direct heat where possible.
>
> Then when tasting the fitment of the new EFI throttle body and the
> existing air breather it became evident that I would need to make some
> adjustments
> to make everything fit comfortably under the hatch. (I do not want to
> raise the hatch above the floor line)
>
> As a side note, when you read that these systems are a direct fit - bolt
> on system, the system might fit but the accessories you require will
> probably
> need modification. This system requires a fair bit of playing with and
> adjusting to make things fit properly.
>
> When it became obvious that I would not be able to make the throttle body
> and existing air breather assembly fit without modifying the hatch and the
> assembly due to the fixed fuel return port on the EFI, I decided to
> re-consider the carb once again.
>
> Thinking this challenge through raised the option of a cold-air intake
> system with a ultra low profile air plenum / carb hat. This would allow for
> the
> EFI to mount on the intake while providing air from a cone style filter on
> the end of a snorkel positioned down in a area which will receive good air
> flow, while not interfering with the floor hatch.
>
> I can design and weld up a custom low profile air plenum which will fit
> but do I require a specific amount of space in the air plenum to make this
> all
> work, CFM?
>
> Will I need an MAF sensor? (I'm not sure if the Fitech has one built-in)
>
> Has anyone else experienced this and which air filter did you use?
>
> As always thanks for your experience and suggestions,
>
> Regards,
> Mike
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: [GMCnet] EFI vs Carb [message #326444 is a reply to message #326442] Tue, 28 November 2017 14:33 Go to previous messageGo to next message
johnd01 is currently offline  johnd01   United States
Messages: 354
Registered: July 2017
Location: Sacrameot
Karma: -1
Senior Member
But i-tank pumps are harder to replace.

On Tue, Nov 28, 2017 at 11:17 AM, Jon Roche wrote:

> You need to do some more research as many have easily installed without
> raising the hatch. It does require normally a remote air filter. I
> think
> applied has some varients that should be complete kits.
>
> No need for maf sensor, just need to get filtered air to the fi-tech.
>
> Fuel delivery is the wild card as there are people happy with the fcc,
> and others have experienced issues.
>
> Call those that have some miles on there setup. Lots of work, but i
> think the best way is to get in-tank pumps. I do not hear of problems with
> people get in-tank pumps. Sure the pump can die, but all pumps can die.
> --
> Jon Roche
> 75 palm beach
> St. Cloud, MN
> http://lqqkatjon.blogspot.com/
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>



--

*John Phillips*
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Johnd01 John Phillips Avion A2600 TZE064V101164 Rancho Cordova, CA (Sacramento)
Re: [GMCnet] EFI vs Carb [message #326445 is a reply to message #326444] Tue, 28 November 2017 14:53 Go to previous messageGo to next message
Emery Stora is currently offline  Emery Stora   United States
Messages: 959
Registered: January 2011
Karma: 4
Senior Member
True, but how often are you planning to replace them?

Mine have been in for 8 years now and are still working fine.

If one were to fail then I still have the other — or if I didn’t have the time to replace an in-tank one I could always hook up an outside the tank one temporarily. The in-tank pumps do allow fuel to be pulled through it by an external pump.

The in-tank pump in my 1973 Jeep Grand Cherokee still worked after 42 years when I traded it in. How many of you have ever had to replace an electric in-tank pump in their automobile?

Emery Stora
77 Kingsley
Frederick, CO


> On Nov 28, 2017, at 1:33 PM, John Phillips wrote:
>
> But i-tank pumps are harder to replace.
>
> On Tue, Nov 28, 2017 at 11:17 AM, Jon Roche wrote:
>
>> You need to do some more research as many have easily installed without
>> raising the hatch. It does require normally a remote air filter. I
>> think
>> applied has some varients that should be complete kits.
>>
>> No need for maf sensor, just need to get filtered air to the fi-tech.
>>
>> Fuel delivery is the wild card as there are people happy with the fcc,
>> and others have experienced issues.
>>
>> Call those that have some miles on there setup. Lots of work, but i
>> think the best way is to get in-tank pumps. I do not hear of problems with
>> people get in-tank pumps. Sure the pump can die, but all pumps can die.
>> --
>> Jon Roche
>> 75 palm beach
>> St. Cloud, MN
>> http://lqqkatjon.blogspot.com/
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
>
> --
>
> *John Phillips*
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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Re: [GMCnet] EFI vs Carb [message #326446 is a reply to message #326445] Tue, 28 November 2017 15:03 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
Sorry, that was a 1993 Jeep Grand Cherokee but that’s still 22 years and 300,000 miles of usage on the original in-tank fuel pump.

The eight year old ones in my GMC now have about 130,000 miles on them.

Emery Stora

> On Nov 28, 2017, at 1:53 PM, Emery Stora wrote:
>
> True, but how often are you planning to replace them?
>
> Mine have been in for 8 years now and are still working fine.
>
> If one were to fail then I still have the other — or if I didn’t have the time to replace an in-tank one I could always hook up an outside the tank one temporarily. The in-tank pumps do allow fuel to be pulled through it by an external pump.
>
> The in-tank pump in my 1973 Jeep Grand Cherokee still worked after 42 years when I traded it in. How many of you have ever had to replace an electric in-tank pump in their automobile?
>
> Emery Stora
> 77 Kingsley
> Frederick, CO
>
>
>> On Nov 28, 2017, at 1:33 PM, John Phillips wrote:
>>
>> But i-tank pumps are harder to replace.
>>
>>> On Tue, Nov 28, 2017 at 11:17 AM, Jon Roche wrote:
>>>
>>> You need to do some more research as many have easily installed without
>>> raising the hatch. It does require normally a remote air filter. I
>>> think
>>> applied has some varients that should be complete kits.
>>>
>>> No need for maf sensor, just need to get filtered air to the fi-tech.
>>>
>>> Fuel delivery is the wild card as there are people happy with the fcc,
>>> and others have experienced issues.
>>>
>>> Call those that have some miles on there setup. Lots of work, but i
>>> think the best way is to get in-tank pumps. I do not hear of problems with
>>> people get in-tank pumps. Sure the pump can die, but all pumps can die.
>>> --
>>> Jon Roche
>>> 75 palm beach
>>> St. Cloud, MN
>>> http://lqqkatjon.blogspot.com/
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>>
>>
>>
>> --
>>
>> *John Phillips*
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

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Re: [GMCnet] EFI vs Carb [message #326449 is a reply to message #326446] Tue, 28 November 2017 15:57 Go to previous messageGo to previous message
sgltrac is currently offline  sgltrac   United States
Messages: 2797
Registered: April 2011
Karma: 1
Senior Member
I had to do an in tank pump in a suburban (99 with 140k)

Know of several other gm in tank pump models with same issue. It’s not
terribly uncommon with gm stuff of that and newer vintage. Astro vans come
to mind. But if you have two pumps ( one in each tank) you would not have
to mess with it until you got home. Which is a lot better than climbing
under the rig and beating on the tank to spur the pump.

Sully
77 eleganza 2
Bellevue.

On Tue, Nov 28, 2017 at 1:04 PM Emery Stora wrote:

> Sorry, that was a 1993 Jeep Grand Cherokee but that’s still 22 years and
> 300,000 miles of usage on the original in-tank fuel pump.
>
> The eight year old ones in my GMC now have about 130,000 miles on them.
>
> Emery Stora
>
>> On Nov 28, 2017, at 1:53 PM, Emery Stora wrote:
>>
>> True, but how often are you planning to replace them?
>>
>> Mine have been in for 8 years now and are still working fine.
>>
>> If one were to fail then I still have the other — or if I didn’t have
> the time to replace an in-tank one I could always hook up an outside the
> tank one temporarily. The in-tank pumps do allow fuel to be pulled through
> it by an external pump.
>>
>> The in-tank pump in my 1973 Jeep Grand Cherokee still worked after 42
> years when I traded it in. How many of you have ever had to replace an
> electric in-tank pump in their automobile?
>>
>> Emery Stora
>> 77 Kingsley
>> Frederick, CO
>>
>>
>>> On Nov 28, 2017, at 1:33 PM, John Phillips
> wrote:
>>>
>>> But i-tank pumps are harder to replace.
>>>
>>>> On Tue, Nov 28, 2017 at 11:17 AM, Jon Roche
> wrote:
>>>>
>>>> You need to do some more research as many have easily installed without
>>>> raising the hatch. It does require normally a remote air filter. I
>>>> think
>>>> applied has some varients that should be complete kits.
>>>>
>>>> No need for maf sensor, just need to get filtered air to the fi-tech.
>>>>
>>>> Fuel delivery is the wild card as there are people happy with the fcc,
>>>> and others have experienced issues.
>>>>
>>>> Call those that have some miles on there setup. Lots of work, but i
>>>> think the best way is to get in-tank pumps. I do not hear of problems
> with
>>>> people get in-tank pumps. Sure the pump can die, but all pumps can
> die.
>>>> --
>>>> Jon Roche
>>>> 75 palm beach
>>>> St. Cloud, MN
>>>> http://lqqkatjon.blogspot.com/
>>>>
>>>> _______________________________________________
>>>> GMCnet mailing list
>>>> Unsubscribe or Change List Options:
>>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>>
>>>
>>>
>>>
>>> --
>>>
>>> *John Phillips*
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
> _______________________________________________
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Sully 77 Royale basket case. Future motorhome land speed record holder(bucket list) Seattle, Wa.
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