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69 GT350 carb spacer

Discussion in '1965-1970 Shelby Mustang GT350 & GT500' started by 69Hertz, Feb 13, 2011.

  1. Feb 13, 2011 #1
    69Hertz

    69Hertz Member

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    I'm trying to define the correct carb spacer for a 69 GT350... 351w with a autolite 4300 carb... Was it 1" or .280" thick???
    thanks....
     
    69Hertz, Feb 13, 2011
    69Hertz, Feb 13, 2011
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  2. Feb 13, 2011 #2
    69Hertz

    69Hertz Member

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    [​IMG]

    is this the correct looking one?
     
    69Hertz, Feb 13, 2011
    69Hertz, Feb 13, 2011
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  3. Feb 13, 2011 #3
    Bob Gaines

    Bob Gaines Well-Known Member

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    Current thinking indicates there were at least two different types. It depends on when the car was built at Ford. The picture you posted depicts the later version used sometime after March 69 which is the best guess at this time.Here is a picture of the all Bakelite plate with the short nipple that was prone to breakage which was probably why the later spacer type with the long contoured steel tube evolved. Bob
     

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    Bob Gaines, Feb 13, 2011
    Bob Gaines, Feb 13, 2011
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  4. Feb 14, 2011 #4
    69Hertz

    69Hertz Member

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    Thanks Bob... When I bought the car 10 years ago it had a Holley carb on it..
    I just bought a "correct" 4300 from Pony Carbs and was at a loss on the spacer. I'm trying to get it as "correct" as possible putting the heat tubes on for the choke etc etc.
    From what I could find all the parts catalogs say for a 351W it's a 1" spacer but then again they're not Shelby specific with the aluminum intake.
    My concern was that I wasn't sure if the gasket needed to seal around all 4 venturi openings. The 1" thick spacers I see in the catalogs all have 4 distinct holes, where as the one currently on my car is "open". My concern is will I get some sort of vacumm leak with the openings in the spacer between the venturi's??
    Thanks for the help and the phone call....
     
    69Hertz, Feb 14, 2011
    69Hertz, Feb 14, 2011
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  5. Feb 14, 2011 #5
    Bob Gaines

    Bob Gaines Well-Known Member

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    The 1 inch spacers may be correct for a cast iron intake but not a Shelby. The added height of the Shelby highrise intake required the different spacers the same as it did on the Boss 302. The Boss 302 only used the later style . Both types of spacer early vs later are the same thickness. The short nozzle that was prone to breakage during installation and removal probably was the reason for the change. There was also another throttle bracket that was sometimes used with the early style spacer . It had a bulge in the middle for more clearance .
     
    Bob Gaines, Feb 14, 2011
    Bob Gaines, Feb 14, 2011
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  6. Feb 14, 2011 #6
    69Hertz

    69Hertz Member

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    Bob, thanks again for sharing your knowledge.. got it all hooked up and the car running tonight.. kudo's for the people at pony carbs, the car started and idled like it was fuel injected. From cold start it went into a perfectly smooth idle right out of the box. It has never run this good..
     
    69Hertz, Feb 14, 2011
    69Hertz, Feb 14, 2011
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