4.8 MPG

what do the new class A gas MHs get?

On Wed, Sep 20, 2017 at 2:48 PM, Chris Tyler
wrote:

> Just to make you feel better, contemporary [to GMC MH] SOB class As
> usually only got 4-5 mpg routinely
> --
> 76 Glenbrook
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
 
what do the new class A gas MHs get?

On Wed, Sep 20, 2017 at 2:48 PM, Chris Tyler
wrote:

> Just to make you feel better, contemporary [to GMC MH] SOB class As
> usually only got 4-5 mpg routinely
> --
> 76 Glenbrook
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:

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We AVERAGE 8.9.......traveling empty or loaded to the hilt and towing the trailer with the Harley & Kayaks.....8.9.
 
So I got the 4.8 in an area with a lot of hills and I wasn't being nice to the coach, I was going up them at 60, same as on the flats.

On the way home I left the cruise off and let the speed sag on hills keeping the vacuum above 10, that got me above 8.

I have a wide band O2 that tells me I'm running 15.5-16.0 to 1 AFR, so it's not overly rich.

as I put the throttle down it richens up till it gets into the 13's at WOT

What do you do on hills to get an average of 8-9?
........i
 
Jerry,

Randy Van Winkle gave presentation at the Elkhart GMCMI Convention and noted that he runs his coach with EFI at that range
consistently.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808

-----Original Message-----
From: Gmclist [mailto:gmclist-bounces] On Behalf Of Gerald Work
Sent: Thursday, September 21, 2017 5:50 PM
To: gmclist
Subject: [GMCnet] 4.8 MPG

I would consider 15.5 to 16:1 too lean given the alcohol in today's gasoline and also think 13:1 under WOT is still not rich enough.
I would be more comfortable if you were in the 12s under those conditions.

Stoichiometric (complete combustion) is a ratio of 14.7:1 only for unadulterated gasoline, not for this crap gas we have to use.
Going 15.5 to 16 for any protracted period of time given the loads our coaches see could result in piston or valve damage,
especially if spark goes away from the planned curve for any reason at the same time.

Where we live in Southern Oregon one needs to climb mountain passes in any direction. I drove up hill without ever allowing the
vacuum to go below 4" (we sold both our GMCs so now have to write in past tense). If the grade was too steep to maintain 4" And 45
MPH I shifted down. That rarely happened with either coach and we took them all over North America from Alaska to Mexico and from
the west coast to the Maritime Provences in eastern Canada.

I found that lightening up on the accelerator while going up hill did not reduce speed all that much but it sure improved vacuum and
reduced the engine load. I think WOT for our engines under load with crap gas, or running too lean, or running too far advanced, is
a recipe for bad stuff to happen. My experience, anyway.

Jerry Work
The Dovetail Joint
Fine furniture designed & hand crafted
in the 1907 former Masonic Temple building
in historic Kerby, OR
http://jerrywork.com
........
 
Here's a good explanation of how to run lean without burning up your engine. You can cool the combustion with excess air or excess fuel. Note this
only works at cruise power and with good control of the lean mixture.

https://www.avweb.com/news/pelican/182084-1.html

Hal Kading 78 Buskirk Las Cruces NM also with a 550 ci 300 hp powered aircraft that has been operated lean of peak egt at cruise for hundreds of
hours.
 
Jerry,

Randy Van Winkle gave presentation at the Elkhart GMCMI Convention and noted that he runs his coach with EFI at that range
consistently.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808
........
 
I'm with you Jerry. I'd much prefer a 1mpg drop (or lack of gain I suppose) to a new engine.
Just not an envelope that's worth pushing to me.

Somewhat related:
When I was running around out west I found that richening up the mixture a tad to about 12.5:1 made a nice difference on hill pulling power. I forgot
to reset it and noticed a good dip in mileage once I got back east!
--
Justin Brady
http://www.thegmcrv.com/
1976 Palm Beach 455
 
Hmmmm. I seem to remember Randy and George replacing cylinder heads
somewhere in the middle of a cross country trip because of a "lean cruise
experiment". I for one, will back the timing down a bit, and go with a rich
fuel mixture on my coach. A couple of miles per gallon is not worth a
beside the road overhaul to me. But, what the heck, America is still a free
country, spend your retirement income any way you choose, before the
Government figures out a way to extract more money from you by taxing that
too.
Jim Hupy, In Canada at Harrison Hot Springs with a bunch of our GMC friends.

> Hi Rob,
>
> I'm glad it is working for him as he is a good friend and I respect his
> ability to diagnose on the fly if something were to go wrong at those lean
> a/f ratios. I doubt that the majority of our owners, including me, could,
> so I preferred to run both of our coaches richer for the kind of driving we
> do/did. I will gladly pay a bit more for fuel to avoid having to replace
> engines.
>
> Larry's findings about a bad canister causing icing on his set up is also
> interesting for this conversation. Our coaches show so many variations at
> this ripe young age of 40 that it I find it hard to diagnose much of
> anything without being hands on. Guess that is why I approached both our
> GMCs with such conservatism.
>
> Jerry
>
> Jerry Work
> The Dovetail Joint
> Fine furniture designed & hand crafted
> in the 1907 former Masonic Temple building
> in historic Kerby, OR
> http://jerrywork.com
> .........
> Date: Thu, 21 Sep 2017 20:32:00 -0500
> From: "Rob Mueller"
> To:
> Subject: Re: [GMCnet] 4.8 MPG
> Message-ID:
> Content-Type: text/plain; charset="us-ascii"
>
> Jerry,
>
> Randy Van Winkle gave presentation at the Elkhart GMCMI Convention and
> noted that he runs his coach with EFI at that range
> consistently.
>
> Regards,
> Rob M.
> The Pedantic Mechanic
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
> USA '77 Kingsley - TZE 267V100808
> ........
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Jerry
Apparently you don't know the whole story about this.
Randy has the Howell TBI system with the EBL added on. With the addition of a variable speed sensor one can go into lean cruise mode which allows leaner fuel mixtures. That can only occur at specific conditions such as cruise speed with a high vacuum and a light foot on the gas peddle. As soon as you get a load on the engine the computer enriches the mixture to what you have with a carb.
There is no need to "diagnose on the fly" as the TBI computer does it automatically.
Randy is not the only one doing this. Many, many of us, including me, have been using this system for many years and go to a higher air fuel mixture under certain cruising conditions.

The greater amount of air keeps the engine as cool as a surplus of fuel.

One gets better gas mileage when the system is in cruise mode and no harm is done to the engine. The system includes a screen for your computer display (optional) that shows several things including speed, MPG, vacuum, gallons consumed, and even cylinder temperature if you add a temperature probe. But it goes in and out of lean cruise automatically.

Emery Stora
77 Kingsley
Frederick, CO

>
> Hi Rob,
>
> I'm glad it is working for him as he is a good friend and I respect his ability to diagnose on the fly if something were to go wrong at those lean a/f ratios. I doubt that the majority of our owners, including me, could, so I preferred to run both of our coaches richer for the kind of driving we do/did. I will gladly pay a bit more for fuel to avoid having to replace engines.
>
> Larry's findings about a bad canister causing icing on his set up is also interesting for this conversation. Our coaches show so many variations at this ripe young age of 40 that it I find it hard to diagnose much of anything without being hands on. Guess that is why I approached both our GMCs with such conservatism.
>
> Jerry
>
> Jerry Work
> The Dovetail Joint
> Fine furniture designed & hand crafted
> in the 1907 former Masonic Temple building
> in historic Kerby, OR
> http://jerrywork.com
> .........
> Date: Thu, 21 Sep 2017 20:32:00 -0500
> From: "Rob Mueller"
> To:
> Subject: Re: [GMCnet] 4.8 MPG
> Message-ID:
> Content-Type: text/plain; charset="us-ascii"
>
> Jerry,
>
> Randy Van Winkle gave presentation at the Elkhart GMCMI Convention and noted that he runs his coach with EFI at that range
> consistently.
>
> Regards,
> Rob M.
> The Pedantic Mechanic
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
> USA '77 Kingsley - TZE 267V100808
> ........
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
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
 
Whole Hog is not a fantasy.... Do an Ebay search for a portable LCD projector with an HDMI interface. (Spend about $40.00 or so).... We are staring out a perfect screen.... Don't know if it is daylight readable though.

----- Original Message -----

From: "James Hupy"
To: "gmclist"
Sent: Thursday, September 21, 2017 7:55:25 AM
Subject: Re: [GMCnet] 4.8 MPG

Why not go "whole hog" and make it a heads up display with projection
capability. Then you could read the info off the windshield, where your
eyes should be focused anyway. Just sayin'.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

I'm leaning that way as well. I have a 4 line by 20 character Vacuum
Fluorescent Display that I want to use, which is definitely not PI
compatible. If I could re-position the display, a 5" or 7" touchscreen
could be used. I want to have the display part look like it could have been
installed at Pontiac originally.

----- Original Message -----

From: "John Phillips"
To: "gmclist"
Sent: Wednesday, September 20, 2017 11:38:47 AM
Subject: Re: [GMCnet] 4.8 MPG

Rick,
I vote for the pie. That way you can add more functionality later.
I also vote for GPS rather than speedometer connection. It should be more
accurate and easier to integrate to the MH.
Here is an instructables link
http://www.instructables.com/id/Raspberry-Pi-GPS-Tracker/
and here is a $20 GPS GPS USB dongle
https://jet.com/product/detail/e1edbb89de4e4ce3add7f632c1995f
25?jcmp=pla:ggl:NJ_dur_Gen_Electronics_a3:Electronics_
GPS_Navigation_GPS_System_Accessories_a3:na:PLA_785706713_43735003609_aud-
303405841869:pla-307670825895:na:na:na:2&code=PLA15&pid=
kenshoo_int&c=785706713&is_retargeting=true&clickid=43cd3370-05e7-4ce6-8dfb-
d3abbda5f03e
used in that project.

There are many other GPS solutions
With the pi you should be able to run data through a spreadsheet to do a
bunch of math, pick out the pertinent data and store it in a different
sheet then zero the original sheet and do it again. Lessor boards are not
compatible with this kind of approach.

> Started working on just such a project. Found a fuel rated flow meter at
> futurelec for about $20.00. I also will need to upgrade my speedometer
with
> an electronic one so that I can get pulses to count (for speed). Planning
> on using either an Arduino Mega or a Rasberry Pi control computer, screen
> will be a Nextion 3.5" touchscreen. Computer parts will be less than $100.
> Don't know what the newer Autometer speedometer setup will cost yet.
>
> ----- Original Message -----
>
> From: "John Phillips"
> To: "gmclist"
> Sent: Tuesday, September 19, 2017 7:44:56 PM
> Subject: Re: [GMCnet] 4.8 MPG
>
> Anyone dream of a car computer that shows instantaneous MPG and range left
> in the tank?
>

>
> > I gave up checking mpg. I got from 12 - 6 mpg on the same trip. (mostly
> > flat) I can never be sure how much my fill-up is because of pump nozzles
> and
> > how I hold my mouth.
> >
> > --
> > Patti & Jerry Burt
> > 73 Gmc 26' Canyon Lands -
> > 77 Palm Beach
> > Members: FMCA - GMCMI - GMCWS - Pacific Cruisers - 49ers
> >
> > _______________________________________________
> > 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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>

--

*John Phillips*
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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”.

>
> 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
1973 23 GMC Glacier
Howell EFI/EBL
 
HUD is known technology. Fighter aircraft started the idea, then commercial
and private aviation, now it has trickled down to automobiles. Aftermarket
suppliers now can fix you up with just about any technology your heart
desires. All it takes is GMC bucks. I figure anything that keeps your eyes
on the road and off the dashboard is a good thing. Inattentive drivers
cause lots of problems on the road, and they are not all using hand held
devices. Old farts with too many gages are just as much of a hazard.
Jim Hupy
Salem, OR
78 GMC ROYALE 403

> Whole Hog is not a fantasy.... Do an Ebay search for a portable LCD
> projector with an HDMI interface. (Spend about $40.00 or so).... We are
> staring out a perfect screen.... Don't know if it is daylight readable
> though.
>
>
> ----- Original Message -----
>
> From: "James Hupy"
> To: "gmclist"
> Sent: Thursday, September 21, 2017 7:55:25 AM
> Subject: Re: [GMCnet] 4.8 MPG
>
> Why not go "whole hog" and make it a heads up display with projection
> capability. Then you could read the info off the windshield, where your
> eyes should be focused anyway. Just sayin'.
> Jim Hupy
> Salem, Or
> 78 GMC ROYALE 403
>

>
> I'm leaning that way as well. I have a 4 line by 20 character Vacuum
> Fluorescent Display that I want to use, which is definitely not PI
> compatible. If I could re-position the display, a 5" or 7" touchscreen
> could be used. I want to have the display part look like it could have been
> installed at Pontiac originally.
>
> ----- Original Message -----
>
> From: "John Phillips"
> To: "gmclist"
> Sent: Wednesday, September 20, 2017 11:38:47 AM
> Subject: Re: [GMCnet] 4.8 MPG
>
> Rick,
> I vote for the pie. That way you can add more functionality later.
> I also vote for GPS rather than speedometer connection. It should be more
> accurate and easier to integrate to the MH.
> Here is an instructables link
> http://www.instructables.com/id/Raspberry-Pi-GPS-Tracker/
> and here is a $20 GPS GPS USB dongle
> https://jet.com/product/detail/e1edbb89de4e4ce3add7f632c1995f
> 25?jcmp=pla:ggl:NJ_dur_Gen_Electronics_a3:Electronics_
> GPS_Navigation_GPS_System_Accessories_a3:na:PLA_785706713_43735003609_aud-
> 303405841869:pla-307670825895:na:na:na:2&code=PLA15&pid=
> kenshoo_int&c=785706713&is_retargeting=true&clickid=
> 43cd3370-05e7-4ce6-8dfb-
> d3abbda5f03e
> used in that project.
>
> There are many other GPS solutions
> With the pi you should be able to run data through a spreadsheet to do a
> bunch of math, pick out the pertinent data and store it in a different
> sheet then zero the original sheet and do it again. Lessor boards are not
> compatible with this kind of approach.
>
>

>
> > Started working on just such a project. Found a fuel rated flow meter at
> > futurelec for about $20.00. I also will need to upgrade my speedometer
> with
> > an electronic one so that I can get pulses to count (for speed). Planning
> > on using either an Arduino Mega or a Rasberry Pi control computer, screen
> > will be a Nextion 3.5" touchscreen. Computer parts will be less than
> $100.
> > Don't know what the newer Autometer speedometer setup will cost yet.
> >
> > ----- Original Message -----
> >
> > From: "John Phillips"
> > To: "gmclist"
> > Sent: Tuesday, September 19, 2017 7:44:56 PM
> > Subject: Re: [GMCnet] 4.8 MPG
> >
> > Anyone dream of a car computer that shows instantaneous MPG and range
> left
> > in the tank?
> >
> > On Tue, Sep 19, 2017 at 5:27 PM, Jerry Burt

> >
> > > I gave up checking mpg. I got from 12 - 6 mpg on the same trip. (mostly
> > > flat) I can never be sure how much my fill-up is because of pump
> nozzles
> > and
> > > how I hold my mouth.
> > >
> > > --
> > > Patti & Jerry Burt
> > > 73 Gmc 26' Canyon Lands -
> > > 77 Palm Beach
> > > Members: FMCA - GMCMI - GMCWS - Pacific Cruisers - 49ers
> > >
> > > _______________________________________________
> > > 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
> >
>
>
>
> --
>
> *John Phillips*
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
> _______________________________________________
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> Hmmmm. I seem to remember Randy and George replacing cylinder heads
> somewhere in the middle of a cross country trip because of a "lean cruise
> experiment". I for one, will back the timing down a bit, and go with a rich
> fuel mixture on my coach. A couple of miles per gallon is not worth a
> beside the road overhaul to me. But, what the heck, America is still a free
> country, spend your retirement income any way you choose, before the
> Government figures out a way to extract more money from you by taxing that
> too.

I'm on my way home from Elkhart and have limited time here but since my name has come up several times I want to clarify a few things.

First, Jim, neither George and I have replace cylinder heads on any trip and neither of us has experienced any issues with running with a lean
mixture. I DO NOT want the wrong information to get out or the inference that lean cruise has or is causing issues with our engines. I did pull one
head to replace a valve but the final diagnosis of that was a failed spark plug that caused some mis-firing heating the back side of the intake valve
causing it to extrude (tulip) then that cylinder went dead. Replaced the valve and now after 25,000 miles not a bit trouble. When the head was open,
a close inspection revealed no evidence of excessive heat or even the hint of any damage. I have put over 100,000 miles on this engine running lean
cruise most of the time.

Everyone has their opinions on what AFR is best to run. I use the EBL upgrade on the 7747 GM ECM. That provides the ability to run under lean cruise
during light cruise conditions. I run as high as 16.5 but the ECM monitors several conditions as Emery stated and will richen the mixture based on
load. As load increases, if you don't richen the mixture then temperatures can climb at a rate that is scary. I would not advocate that a carbureted
engine go very lean as you do not have a computer that is reacting in nano-seconds to make AFR changes. If you jet a carb to run at 16.2, then based
on what George and I have observed, it will start getting really hot (hot enough to melt something) and will do it quickly unless you are on it enough
to kick in the secondaries. Once you start dumping in fuel the temps will stabilize. What we learned is that once additional fuel is introduced,
temps stop climbing but it will not go back down during the loaded interval. In our case, the computer monitors load and starts riching the mixture
as load increases until it gets back to 14.7 AFR. As load continues to increase, the computer goes into Power Enrichment (Secondaries) going to around
13.8 initially, then continues to richen mixture as load continues over time. I have seen the resulting mixture get down to around 12 to 1 and a
couple of times in the high 11s. With a carburetor you do not have this kind of control so if you are going to play with AFR, I suggest a WB O2 sensor
as well as Exhaust Gas Temperature (EGT) probes. That way you can monitor and possibly avoid engine damage. One other point: When we change to lean
cruise we limit the ratio to 16.5 to 1. I would never go this high with a carburetor or some of the aftermarket EFI units. Unless you are also
changing Spark Advance (SA) as you go into lean cruise you will start losing the ability to make sufficient power at around 16.2 to 1 in our coaches
(might get away will slightly more in a car). By advancing the timing, you can continue to make good power to up around 17 to 1. After that, the
mixture is too lean and you cannot keep our heavy coaches moving and the engine starts to struggle. At 16.5 to 1 AFR, I advance the timing by an
additional 5 degrees. This EBL computer has the ability to do this. So, as AFR gets leaner, the SA advances more in parallel and goes the other way
as load increases. All done automatically - I never have to think about whether a problem is lurking or not.

Bottom line, don't mess with lean cruise unless you have a fuel injection system that is set up with the logic to manage that environment. If you
still want to go lean during cruise, be sure to get a WB O2 sensor and EGT gauges so you can monitor the results. I do state in my fuel injections
sessions at rallies that I am running lean cruise but try to qualify the fact that it is under computer control and done after a lot of testing.

And, I agree with what Jerry Work has said except that I believe that lean cruise is possible (if done correctly) without damaging our engines. Look
at Hal Kading's post. Aviation guys have been doing this for years - even doing it manually but they get a lot of training on how to monitor and
adjust properly.

--
Randy & Margie
'77 Eleganza II '403'
Battlefield, MO
 
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

> 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”.
>
>

> >
> > 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
> 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
>
 
The thread has drifted a bit. My initial post was in response to someone who indicated they were running very lean (16.x) in normal operation (at least that was my interpretation of what they said). I didn't want new owners to read that and think it ok to run that lean all the time.

I know some of the EFI units with reliable knock sensors and the smarts to do so can go into lean cruise with appropriate spark advance and get to those levels under ideal low load conditions, conditions we on the west coast don't see as often. So, from my experience, a lot of the discussion about various EFI and carb tuning topics over the years is very much colored by where and how one drives. All the options appear to work for someone, but no one solution seems optimum for everyone.

I remain a staunch advocate for all the drivability gains one can experience from EFI, but when asked, recommend the simpler modern self learning systems for our new GMC owners. Older hands, those with lots of ancient big iron engine experience, and those interested in squeezing out all the fuel economy to be had in our coaches will likely prefer the greater hands on control offered by systems like the Howell with EBL alternatives.

'nuff said from my POV........

Jerry Work
The Dovetail Joint
Fine furniture designed & hand crafted
in the 1907 former Masonic Temple building
in historic Kerby, OR
http://jerrywork.com
 
Can someone tell me how in He-double hockey sticks, we have 7 different
conversations all with the subject line 4.8 MPG ???

Mike in NS

--
Michael Beaton
1977 Kingsley 26-11
1977 Eleganza II 26-3
Antigonish, NS

Life is too short to hold a grudge; slash some tires and call it even !
 
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