When I put the 292 in my 55 I will have have a few choices for a carb and will eliminate the Holley teapot so it will either be the 56 merc Carter or a 57 intake with a modern carb,I prefer mechanical secondaries and the Merc Carter 4 bbl is vacumn so does anyone know if I can take parts from a GM version (which I should have somewhere in the shed) and convert it as I doubt the secondary diaphram is readily available and cheap.   I will most likely use a 57 intake and modern carb but if I want a old look might consider the carter and was wondering if anyone used that carb and how did they work and are they any better then the teapot and can I get parts to rebuild it.

Butchering up everything I can get my hands on in Dayton Ohio

The Carter will work fine, but I'd think hard about changing it to mechanical secondaries on a street machine. the vacuum actually works pretty well in that situation.

Frank/Rebop

Bristol, In ( by Elkhart) 

You might try these guys for hard to get carb parts and/or kits.  They can also make new or replacement diaphragms if you have the old diaphragm.

http://www.daytonaparts.com/

Lorena, Texas (South of Waco)

You can get a '57 looking carb from Holley, new. I'm sure aficionados would notice the difference but someone like me will never know the difference.


Lawrenceville, GA

The Carter is a very good carburetor. It is much more difficult to rebuild than a Holley due to the metering rods have to be set with gauges and linkages have to be bent for proper settings, however it will out do a Holley anytime when built right. 56 Merc rated their 312's at 235HP and 312's with Holley's at 225 HP only difference was the carb.

The diaphragm is still available however you will have to install the linkage rod as it is only the diaphragm sold. I have seen very few diaphragms that needed replacement on that particular Carter. They can be re-used several times.

These guys I bought the last set from.
http://www.carburetor.ca/
marv

Looks to me like you could just install the gm Carter.  As I remember them, the secondary linkage is mechanical, but above the secondary throttle plates are another set of plates that are counterbalanced and require a predetermined amount of manifold vacuum to open them, so in a sense these are also vacuum secondary carbs, just no diaphragm.

John - "The Hoosier Hurricane"

John, That's definitely the way the newer thermoquad, and the still newer "Edelbrock" Carter carburetors work. Secondaries are mechanical but the have a vacuum operated air valve above them. I guess a '56 would be an afb which I know little about.


Lawrenceville, GA

Marv

Thats not quite correct.

The Merc used a different camshaft.See Ford service bulletin # M-118a for the specifics.

Oldmics

Jeff: Just for info, YBM recently published in issue #97 a 16 carb test of 4bbls done by our moderator Ted Eaton. It included the original Carter that you are asking about. The tests included 3 other 1957 carbs or equivalents. The Carter finished dead last. And from all I've learned, I have to agree with those who are advising you to forget about modifying a street carb to mechanical secondaries. It's old thinking that doesn't work..

Paul

I looked it over and resembles a Rochester 4GC and nothing like a AFB,I knew Ford took designs from carb manufactures and it looks like GM did it too.  The more I think about it I will use a edelbrock carb on a 57 intake.

Butchering up everything I can get my hands on in Dayton Ohio