SAAC Forum

The Cars => 1968 Shelby GT350/500/500KR => Topic started by: Coralsnake on February 28, 2021, 07:41:17 PM

Title: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: Coralsnake on February 28, 2021, 07:41:17 PM
The factory only built 112 GT350 automatics with the Holley carburetor.

This meeting note indicates the combination was not certified and it was the intention of SA to replace them.

Some were exchanged. So, it's likely only a very small percentage that survived.

(http://www.saacforum.com/gallery/8-280221193517.jpeg)

Imco = automatic transmissions

GPD = Autolite production carburetor
Title: Re: Why your 1968 GT350 probably didnt have a Holley
Post by: Coralsnake on February 28, 2021, 07:54:45 PM
112 built / 1457 total GT350s = less than 8 % built with Holley and some of those returned.

In other words,  there is greater than 92 %  chance that a GT350 with an automatic transmission would have a Autolite carburetor
Title: Re: Why your 1968 GT350 probably didnt have a Holley
Post by: 68gtcoupe on February 28, 2021, 08:13:09 PM
Nice!  Maybe the value of the Autolite C8ZF-D that's been sitting in a box in my basement just went up a few bucks.
Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: Coralsnake on February 28, 2021, 08:18:18 PM
And it explains why finding a factory installed Holley on a GT350 with an aluminum intake is so hard
Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: KR Convertible on February 28, 2021, 09:50:10 PM
I thought only 4 speed cars got thermactor.
Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: Coralsnake on March 01, 2021, 06:39:16 AM
They did. Thermactor is smog, IMCO is not the same
Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: KR Convertible on March 01, 2021, 09:32:00 AM
I was looking at the last sentence in the first paragraph.  It says "Certificates of conformity have been issued for GPD carburetors with both IMCO and Thermactor systems".
Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: Coralsnake on March 01, 2021, 09:35:36 AM
Yes I read that as certificates for Autolite carbs on 4spds (thermactors) and autos (IMCO).
Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: Bob Gaines on March 01, 2021, 09:37:09 AM
Does the memo indicate that the cars built between job one and 3/22/68 had aluminum intakes given the Holley carbs? 
Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: Coralsnake on March 01, 2021, 09:54:55 AM
This other memo would seem to indicate the aluminum manifolds didnt start until March  15th

I think manifolds and carbs were separate items and not treated as a combo


(http://www.thecoralsnake.com/350recalltr.jpg)
Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: shelbydoug on March 01, 2021, 10:19:08 AM
It says either the Holley or the Autolite carb MAY be used but it doesn't say that it is includded in the recall parts supplied.

Is there evidence to see that shows the S8MS Holley carbs were being installed before May March 15? Sorry, they're both "M" words.  ::)

I haven't seen reference to that at all. The earliest dates on the carbs I have seen are March or April 68 but I've only seen a few carbs.

Most of 68 GT350 production was done by the time the S7MS intake and S8MS Holleys were incorporated into production.
Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: KR Convertible on March 01, 2021, 12:47:45 PM
Do we know what IMCO actually stands for?  GPD?
Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: Coralsnake on March 01, 2021, 01:40:50 PM
Improved combustion, its basically the pcv system

Gpd Im still working on finding that, but its the standard production part
Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: 67_1183 on March 01, 2021, 02:00:42 PM
According to MrFoMoCo:

QuoteThe Autolite name was used for all components released by
Ford's General Products Division (GPD) through model-year
1971. The changeover to Motorcraft - at least for GPD,
which was responsible for Assembly parts - came @ May, 1971.

Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: Coralsnake on March 01, 2021, 02:36:47 PM
I think we have a winner
Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: KR500 on March 01, 2021, 03:08:23 PM
Quote from: Coralsnake on March 01, 2021, 01:40:50 PM
Improved combustion, its basically the pcv system

Gpd Im still working on finding that, but its the standard production part
IMCO has nothing to do with the PCV system. For the 1968 MY it consists of a different distributor advance curve and  leaner carburetor jetting.
Rodney
Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: KR Convertible on March 01, 2021, 03:31:28 PM
So, the GT350 used an Autolite 4300 and the (early) GT500 used an Autolite 4100?
Title: Re: Why your 1968 GT350 / automatic probably didnt have a Holley
Post by: Coralsnake on March 01, 2021, 05:09:56 PM
These are true statements