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Does anyone know if a stock '65 4bbl intake manifold that had the Carter AFB carb accept an Edelbrock 1406 without using a thicker base gasket or adapter plate? Hard to tell from pictures but to my eye it looks like the manifold secondaries are the same size as the primaries whereas the 1406 looks like maybe the secondaries are a bit larger. Anyone done this setup? Thanks.
 

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Does anyone know if a stock '65 4bbl intake manifold that had the Carter AFB carb accept an Edelbrock 1406 without using a thicker base gasket or adapter plate? Hard to tell from pictures but to my eye it looks like the manifold secondaries are the same size as the primaries whereas the 1406 looks like maybe the secondaries are a bit larger. Anyone done this setup? Thanks.

OK, I'll tackle this one.

The '65 Carter is from what I understand 500CFM's. I do believe it may have a smaller base/bolt pattern than the 1406. But, the 1406 should have 2 base/bolt patterns - small and larger width.

In my hand is a 1407 - the 750 CFM version. The primary throttle bore is 1 5/8", but Edelbrock says 1 11/16". The secondary bore does measure 1 11/16" as stated by Edelbrock.

The 1406 is a 600 CFM and Edelbrock shows the primary bores as 1 7/16" and your secondary bore size is 1 11/16" like the 1407 750CFM carb.

Looking at the front of the carb, the spacing between the inner bolt holes is approx. 4 1/4" center of the hole-to-center of the hole. Outer bolt holes are approx. 5 1/8".

Looking at the side, linkage side, the spacing between the bolt holes center-to-center on either the inner or outer bolt holes is approx. 5 5/8".

Looking at the photo of the base, you will need an open in the center flat plate, ie adapter, or a flat manifold surface of 4 1/2" x 4 1/2" square that will seal up against the bottom of the carb base so no vacuum leaks will be created.

Personally, I just spent a little time sorting through the Edelbrock carb choices for my own car's intake/carb set-up. I feel the AVS2 carb is a better choice. The "standard" AFB uses a weighted secondary air flap that is a "one size fits all." I have used the AFB's in the past in a dual quad application without problem. But, if you wanted to cause the secondary air flap to open quicker, you had to grind material off the weights a little at a time and test, and then hope you did not remove too much. Conversely, if you wanted to delay the opening, you had to find a means to add weight to slow the opening of the flap. You also had to remove the top and rear venturi to do this. I never did it, but know how to do it.

However, the AVS2 has a spring loaded secondary air flap just like the Q-jet and is adjusted in the same manner. This means you can better tailor the secondary opening rate to your engine needs by adding or subtracting the spring tension on the secondary air flap.

The other important feature of the AVS2 is the use of an "annular ring" in the primary venturis that atomizes the fuel much better and provides better performance.

They offer the AVS2 in a 650CFM and would be what I would go with on your engine.

The down side of the Edelbrock AFB is that the fuel inlet is on the wrong side for a Pontiac. The carb has the inlet on the passenger side. But Edelbrock has a steel line with a banjo fitting that may work out.

Edelbrock 1407 - 750.JPG
 

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Wow! Alot of great info there Jim. I'll look into the AVS2, but it kinda sounds tricky and complicated on the secondaries and I was hoping for a plug and play carb. Thanks again for your input.
 

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Wow! Alot of great info there Jim. I'll look into the AVS2, but it kinda sounds tricky and complicated on the secondaries and I was hoping for a plug and play carb. Thanks again for your input.
Nothing is "plug & play." That only happens on TV shows where they can do a ground up restoration in 17 days and just by chance have some guy driving past the shop who sees the finished car roll out the garage door and its "just what he was looking for" and pays the asking price - with cash, no doubt.

If you have to use a spacer/adapter, use a 4-hole piece and not an open hole adapter. The 4-hole will provide the needed velocity of the air through the carb and utilize the design of the factory 180 type intake manifold.
 
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