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[GMCnet] Which TBI system to use [message #286886] Tue, 08 September 2015 17:24 Go to next message
Advanced Concept Ener is currently offline  Advanced Concept Ener   United States
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Registered: December 2014
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Ok I am sick and tired of the pre-ignition knock and loss of power based on the outside temp, load and what brand of gas I put in. Got stuck buying Gulf in Mass last week and thought the engine was running on 6 cylinders on the long hills. It sounded like a popcorn machine! Even my wife commented. Need to go to fuel injection with automatic ignition timing control. Looking at Jim K Atomic MSD, Holly Terminator and Fast 2. I know you guys have discussed this to death in the past but 6months in technology is two lifetimes. I would like any advice you could give me before I spend a lot more on this coach. In 1991 I installed a Holly TBI on my 78 Royale and it really was a great improvement. No hesitation, no hiccups, no vapor lock, instant start, smooth operation when compared to a brand new carb. One concern is all that electronics in that really hot engine compartment! I wonder if the atomizing gas actually cools the electronics? I really don't know anything about these new systems. After watching the MSD video twice I don't understand how it could possibly control ignition timing with the connections they show or talk about.

Jon Darcy ACES
North Jersey 76 stretch, flares, 4 bag, Alcoa's, bunkhouse,MAC Dash, new Ken Frey Rebuilt Engine
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Re: [GMCnet] Which TBI system to use [message #286887 is a reply to message #286886] Tue, 08 September 2015 17:41 Go to previous messageGo to next message
ljdavick is currently offline  ljdavick   United States
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One of the reasons I decided to by such a complicated old Motorhome was the fantastic support community of this list.

I always wanted to rid myself of the carb too and so for me the choice was clear. I chose to do what many others here did without much consideration to the rest of the offerings.

I have the Howell EFI with the EBL interface and an electronic distributor. Something under $2,500, I think. It's a big job for this fat shade tree mechanic but she runs beautifully. I need to take some spark out of the tables as it pings on load, but that's all doable from the computer.
It's much more of a kit than some others but I've had wonderful support to get me where I am.

The engine purrs now.

Next stop - Pertronix on the Onan!

Larry Davick
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Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy
Re: [GMCnet] Which TBI system to use [message #286888 is a reply to message #286886] Tue, 08 September 2015 18:29 Go to previous message
George Beckman is currently offline  George Beckman   United States
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Registered: October 2008
Location: Colfax, CA
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Advanced Concept Ener wrote on Tue, 08 September 2015 15:24
Ok I am sick and tired of the pre-ignition knock and loss of power based on the outside temp, load and what brand of gas I put in. Got stuck buying Gulf in Mass last week and thought the engine was running on 6 cylinders on the long hills. It sounded like a popcorn machine! Even my wife commented. Need to go to fuel injection with automatic ignition timing control. Looking at Jim K Atomic MSD, Holly Terminator and Fast 2. I know you guys have discussed this to death in the past but 6months in technology is two lifetimes. I would like any advice you could give me before I spend a lot more on this coach.

Jon Darcy ACES

Jon,

You may be interested in the EFI group for GMCers. You can look here:

https://groups.google.com/forum/?hl=en#!forum/gmcmh-efi


I will say here that many there have the EBL system with spark control. That does not mean we are pushing it or selling it. Many went for the EBL a little at a time. I started with the Howell, then I did my own spark control setup. Meanwhile I was asking Bob Musgrove to make chips for me, trying to get things set up right. Then Randy Van Winkle bought a burner and I bought a bunch of chips. Unfortunately he lives 1900 miles from me so we sent chips back and forth. We learned to take logs so we could figure out what was happening.

When EBL came to our attention we realized that it allowed the chip to be modified without burning or mailing. It also takes logs with the click of a mouse.

The EBL spark control is integrated with the fuel control, meaning when the computer alters the mixture it also makes appropriate spark changes.

The Atomic is a slick system. Bolt on with all electronics in the TBI. There is a provision for spark control. It, as far as I can tell, that more or less emulates a well curved distributor with vacuum and weights. I believe it has a knock sensor capability.

Come to the EFI site and you will find much experience and help there.


'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
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