Fuel injection question for those who have switched.

T

Thigh19

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Aug 4, 2019
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Okay, the Howell fuel injection is the greatest think in the world, I get it. Now to anger a few, I’m using the Fitech fuel injection on 2 of my
vehicles, one being my 73 Sequoia, and have had no problems once I figured out the return line. I know I won’t be able to change anyone’s mind on
this topic, but for the cost of the Howell system, I can buy 3 Fitech complete systems.
 
> Okay, the Howell fuel injection is the greatest think in the world, I get it. Now to anger a few, I’m using the Fitech fuel injection on 2 of my
> vehicles, one being my 73 Sequoia, and have had no problems once I figured out the return line. I know I won’t be able to change anyone’s mind
> on this topic, but for the cost of the Howell system, I can buy 3 Fitech complete systems.

Tom,

I'm glad that you can buy all those systems, but I have two problems.
First is that Fitech is woefully lacking specifics on the website.
While I do see a O2 sensor there, there is no indication of how it is used.
Second, there is no indication that a knock sensor is there, without the loop closure on knock to optimize timing, you do not have engine management,
just a fancy altitude corrected carburetor.

If you can think of an engine management system. If I haven't owned one, was only because my job required that I drive one the company provided.

The reason I still run a quadra-bog (as we call the early generation) is that mine works well. I rarely go over 9KMSL and it still works. Changing
out of a working igntion that reliably fires 0.065 plugs would only have charm if it could controlled by an integral and self calbrating sensor.
Sometime I would like to tell you what we did to include a working knock sensor in any engine family. It is not all that simple to include such a
thing.

Matt writing from the International
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
Tom,
Apparently you do not know that a Fi Tec lacks Distributor control .
Same as what I ran on my cad back in 1988.

> > Okay, the Howell fuel injection is the greatest think in the world, I
> get it. Now to anger a few, I’m using the Fitech fuel injection on 2 of my
> > vehicles, one being my 73 Sequoia, and have had no problems once I
> figured out the return line. I know I won’t be able to change anyone’s mind
> > on this topic, but for the cost of the Howell system, I can buy 3 Fitech
> complete systems.
>
> Tom,
>
> I'm glad that you can buy all those systems, but I have two problems.
> First is that Fitech is woefully lacking specifics on the website.
> While I do see a O2 sensor there, there is no indication of how it is
> used.
> Second, there is no indication that a knock sensor is there, without the
> loop closure on knock to optimize timing, you do not have engine management,
> just a fancy altitude corrected carburetor.
>
> If you can think of an engine management system. If I haven't owned one,
> was only because my job required that I drive one the company provided.
>
> The reason I still run a quadra-bog (as we call the early generation) is
> that mine works well. I rarely go over 9KMSL and it still works. Changing
> out of a working igntion that reliably fires 0.065 plugs would only have
> charm if it could controlled by an integral and self calbrating sensor.
> Sometime I would like to tell you what we did to include a working knock
> sensor in any engine family. It is not all that simple to include such a
> thing.
>
> Matt writing from the International
> --
> Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL,
> GMCES
> Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum
> Brakes with Applied Control Arms
> SE Michigan - Near DTW - Twixt A2 and Detroit
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>

--
Jim Kanomata ASE
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
 
Ladiea, I got a couple questions here. My current coach fits the MSD Atomic. It was a California coach, and I was given to believe CARB would accept
the MSD Atomic. Holley still sells them alongside the Sniper, perhaps because it's certified?
Next up, will CARB accept the Howell setup? If not, it's gonna be relegated to older coaches in California.
Next, there was and may still be an outboard timing box to use with the MSD. Would this give the same improvement as the EBL setup with the Howell?
My coach has two wideband O2 sensors, one feeding the ratio gauge on the dash and the other feeding the MSD Atomic injection. For all of Jim's
mentions, the GM throttle body is the same squirt setup as the all in one units, just differently and perhaps more closely controlled.
Now I put many miles - six digits - on a Kia with direct injection. Gave it to the kid a year ago, it's still doing well. Replaced it with another
Kia, this'n is port injected. The direct injection is the ultimate answer, as long as the proper materials are used in the engine to overcome the
lack of wet intake valve stems. The Kia was the same displacement as my Datsun cammer wagon from the late 60s. Modern manufacturing, camming, and
control give a 35% power increase in a more reliable and longer lived engine. For an eiohtfold price increase over 45 years.

--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
 
Or be a 1975 or older coach in the DMV files.

>
> From what I have been told. Msd atomic is the only efi you might get by with on a california smog check. But if you get the wrong smog check even
> that wont really pass as atomic is carb compliant on other applications and our motorhome is not listed. So if the smog guy pays attention you wont
> pass.
>
> As for spark control, only the gm based has advanced spark control. Used a knock sensor. And has large tables. Others such as the fi-tech, msd
> all just mimic vacuum curve. Small tables.
>
> The new sniper has larger ability for spark control. Not much been played with on that.
>
> Just what i remember from the efi seminar at gmcmi a week ago.
>
> --
> Jon Roche
> 75 palm beach
> EBL EFI, manny headers, Micro Level, rebuilt most of coach now.
> St. Cloud, MN
> http://lqqkatjon.blogspot.com/
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
 
Back in the day of email lists, I had a tagline that said 'God and Carter make good carburetors' and if I ever build up another ride with an RB engine
in it, it will get a properly jetted AFB if I can find one. However, I don't think I'd want to try to get an AFB to pkay nicely on a 455 in a GMC.
The Q-jet did fine in my 23', the MSD injection does fine in my 26'.

--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
 
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