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[GMCnet] Utter disapointment. [message #323680] Sat, 09 September 2017 23:20 Go to next message
BobDunahugh is currently offline  BobDunahugh   United States
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Location: Cedar Rapids, IA
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Utter disappointment in that I hadn't put my Howell EFI system 4 years ago when I bought it. That 403 runs smoother, and stronger. Took it on a short 60 mile trip today. Perfect. I really, really needed that. Bob Dunahugh
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Re: [GMCnet] Utter disapointment. [message #323688 is a reply to message #323680] Sun, 10 September 2017 07:17 Go to previous messageGo to next message
kstockwell is currently offline  kstockwell   United States
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Registered: May 2016
Location: Putney VT
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I've been thinking I want to do this too. Sorry it worked out for you Smile

kelly


1978 Kingsley Putney VT
Re: [GMCnet] Utter disapointment. [message #323699 is a reply to message #323688] Sun, 10 September 2017 11:53 Go to previous messageGo to next message
David del Rio is currently offline  David del Rio   United States
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Registered: April 2016
Location: Raymond CA
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So there is MSD, FiTech, and Howell... perhaps others? Is there a consensus as to the 'best choice' for a novice mechanic who loves his coach and wants to make it the best it can be?

I'm sure there are proponents, and even opponents for each. I'm not trying to start a battle, only to learn what it is that makes one system a better choice than another... so please don't slam one brand or another as members have installed all three and no one want's to be made to feel that they chose poorly.

Thanks much!
Soon to be "Injected Dave"


David del Rio - 75 Avion - Raymond, CA
Re: [GMCnet] Utter disapointment. [message #323701 is a reply to message #323680] Sun, 10 September 2017 13:27 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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I like the EBL system from Dynamic EFI. They only provide the smarter upgrade microprocessor board for the GM Engine Control Module (ECM). I started out with a Howell EFI, which uses a GM ECM programmed for our engines, so you can't effectively adjust it. The EBL replaces the GM ECM and suddenly you get a self learning system with a lot of extra goodies like Lean Cruise and Deceleration fuel cut-off. I changed the Holley TBI to a Rochester one from a 454. Now Except for the EBL, I can buy parts for it anywhere because they are all GM parts.

dynamicefi.com

One major issue I see with the all-in-one package units as an electronics guy is the heat on top of the engine. Electronic components don't like high heat, especially semiconductors which need to dissipate their own heat.

JWID


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
Hubler 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: [GMCnet] Utter disapointment. [message #323704 is a reply to message #323701] Sun, 10 September 2017 13:35 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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Location: Americus, GA
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Bruce,

You and I certainly agree about the all-in-one EFI systems -- DON'T like
all those electronics sitting on top of the hot engine. If I were somehow
persuaded to replace my EFI/EBL with something like FiTech, I'd ONLY do it
if the manifold's exhaust crossover was blocked.

Ken H.

On Sun, Sep 10, 2017 at 2:27 PM, Bruce Hislop wrote:

> ​...
>
> One major issue I see with the all-in-one package units as an electronics
> guy is the heat on top of the engine. Electronic components don't like high
> heat, especially semiconductors which need to dissipate their own heat.
> ​
>
​...
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Utter disapointment. [message #323708 is a reply to message #323680] Sun, 10 September 2017 14:54 Go to previous messageGo to next message
Johnny Bridges is currently offline  Johnny Bridges   United States
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Location: Braselton ga
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Well, >if< they're using parts intended for high heat environments, they will do fine. If they're using consumer grade from the Hung Chow Transistor Works, all bets are off.

--johnny


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" - ol Andy, paraphrased
Re: [GMCnet] Utter disapointment. [message #323732 is a reply to message #323680] Sun, 10 September 2017 19:50 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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Hi Johnny,
I use extended temperature range micros in my equipment, mainly to get the low operating temperature down to -40C, but that only gives me a Tjunction of 125C on the high end. I'm thinking when you shut down to fuel up, the Tambient on top of the engine is going to be up in that range, or maybe more. Upon startup the Tjunction going way above that. I know there are aerospace/military devices with high junction ratings, but they come at high cost... let alone other components like capacitors that don't like heat.

anyway, its a concern and the poster didn't want to get into a slamming contest, so I'll leave it at that.


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
Hubler 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: [GMCnet] Utter disapointment. [message #323746 is a reply to message #323680] Mon, 11 September 2017 00:13 Go to previous messageGo to next message
BobDunahugh is currently offline  BobDunahugh   United States
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Registered: October 2010
Location: Cedar Rapids, IA
Karma: 11
Senior Member
David. We don't fight, or slam each other ever. Love the people here. Each system has their pros, and cons. And it comes down to YOUR comfort zone. I picked the Howell. It's a long tried system that GM started using back in 1987. And you never heard of issues with their components. Mine has the GM 454 TB with the Olds 307 computer controlled Distributor. Not the Holly. The Holly TB is good. But I wanted a total GM setup. As our failures are never at home. And always on the road. It was VERY important for me. To be able to walk into any parts store in North America. And more then likely. They'd have the part I needed NOW. On hand. I thought the system was fairly simple to install. Started right up. Nothing needed adjusting. Had to make some small brackets for components. A down side was that the GM 454 TB required more foot throttle pressure then stock. So I made a 1 inch aluminum bracket that solved that issue. Feels stock now. ( If anyone needs that throttle bracket. Let me know. ) I like the Engine Check light with the test port. A nice chunk of the mileage, and performance comes from the EFI controlled distributor. This Is MY take on the subject.

Bob Dunahugh
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Re: [GMCnet] Utter disapointment. [message #323751 is a reply to message #323746] Mon, 11 September 2017 07:40 Go to previous messageGo to next message
Richard Denney is currently offline  Richard Denney   United States
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Registered: April 2010
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Bob, I envy you for the GM parts houses in your area, but around here
nobody ever has anything in stock NOW. I have to chase all over town to get
even simple things for my (current) cars.

I have a plain old carburetor, but if something in it failed, I'd still
have to jerry-rig something to get home. For example, a choke pulloff at
the local GM (name the brand) dealership? Not in most places. And certainly
not at autoparts stores.

I'm not sure that Holley throttle body would be any less available than a
Rochester throttle body.

This is, of course, the problem with the all-in-one units like FITech. If
something in them fails, you have to replace the whole unit. That's an
expensive spare to carry around. But you can carry the carburetor as a
spare. I think we've seen one sudden and unexpected failure so far. The
other problem with FITech (for some) is that it lacks spark control, but
that makes it an interesting alternative for early coaches that don't have
HEI ignition. It DOES have closed-loop mixture control. And it runs from an
intermediate tank that is fed by existing low-pressure pumps, so if it
fails and you put a carb on the engine, it's easy to get low-pressure to
the carb. And the final advantage is that it is easy--it does not use that
complicated wiring harness.

The heat durability problem of the internal integrated circuits in the
FITech is a problem for me as for others. But there are many on the road
now, so we'll start to get a sense of their durability over the next year
or so, I think. The air coming into the throttle body can be cooler than
the air anywhere in the engine compartment, and they are probably using
that to cool their chips. I think I would plumb a cold-air induction system
if I used the FITech. It would be interesting for someone who has handled
one to inspect it for internal cooling pads or fins.

Rick "who has to special-order everything, it seems" Denney




On Mon, Sep 11, 2017 at 1:13 AM, Bob Dunahugh wrote:

> David. We don't fight, or slam each other ever. Love the people here. Each
> system has their pros, and cons. And it comes down to YOUR comfort zone. I
> picked the Howell. It's a long tried system that GM started using back in
> 1987. And you never heard of issues with their components. Mine has the GM
> 454 TB with the Olds 307 computer controlled Distributor. Not the Holly.
> The Holly TB is good. But I wanted a total GM setup. As our failures are
> never at home. And always on the road. It was VERY important for me. To be
> able to walk into any parts store in North America. And more then likely.
> They'd have the part I needed NOW. On hand. I thought the system was fairly
> simple to install. Started right up. Nothing needed adjusting. Had to make
> some small brackets for components. A down side was that the GM 454 TB
> required more foot throttle pressure then stock. So I made a 1 inch
> aluminum bracket that solved that issue. Feels stock now. ( If anyone
> needs that throttle bracket. Let me know. ) I like the Engine Check light
> with the test port. A nice chunk of the mileage, and performance comes from
> the EFI controlled distributor. This Is MY take on the subject.
>
> Bob Dunahugh
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>



--
'73 X-Glacier 230 "Jaws"
Northern Virginia
Offlist email: rick at rickdenney dot com
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Re: [GMCnet] Utter disapointment. [message #323753 is a reply to message #323680] Mon, 11 September 2017 07:57 Go to previous messageGo to next message
Johnny Bridges is currently offline  Johnny Bridges   United States
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Registered: May 2011
Location: Braselton ga
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Take one apart and see if the semiconductors have 'Unitrode' stamped on them. If Unitrode is still in binniss. Their stuff works in hell heat. And, costs accordingly.


--johnny


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" - ol Andy, paraphrased
Re: [GMCnet] Utter disapointment. [message #323818 is a reply to message #323753] Tue, 12 September 2017 19:47 Go to previous message
dservati1 is currently offline  dservati1   
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Registered: December 2013
Location: Western New York -Rochest...
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Time will tell with the Fitech...I like the all in one option, saving the carb as back up.

Inexperienced Dave


'78 Palm Beach car nut & new to RV'ing 26 ft. 403 OEM wheels, 2 ACs, Pod, ladder, macerator On FaceBook as David Martin 585-953-53OO call or text
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