Carburetor recommendations, please! - 351C, 4BBL

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mustang_maria73

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My car is a 73 convertible with a 351C 4BBL (Q code) and 4 speed manual transmission. Looking for recommendations to replace the 4300D carb (original and works, which I plan to keep in case I ever decide to show it).   FYI, I'm a newbie to car repair/restoration so my knowledge is minimal. 

The car is a survivor car and I want to keep it as original as possible but with a more reliable carb and best performance without mods. Last year Jeff73Mach1 recommended to "put the adapter on it and slap a Holley 700 Double pumper" which sounds good to me.  Any other recommendations before I purchase?  If you need any other specifics to make suggestions, let me know.

 
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Pretty much the same thing, an adapter and new carburetor. If it were me, I would take a look at Summit's own brand of carburetors, nice carburetor, nice price, looks like the old Ford 4100 carburetors. I'm assuming you don't have Ram Air.

 

mustang_maria73

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Pretty much the same thing, an adapter and new carburetor. If it were me, I would take a look at Summit's own brand of carburetors, nice carburetor, nice price, looks like the old Ford 4100 carburetors. I'm assuming you don't have Ram Air.
Thanks, I'll look at those.  I don't have Ram air.  Is there a particular one you would recommend to get max performance/power without additional mods?  Here's the Marti with my car specs if that helps.

.

 

mustang_maria73

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Agree with Don's recommendation.

also, you could swap the intake to a 70-71 iron 4V and nobody would know with the air cleaner in place. Skips the hokey adapter as well.
Do you know if it's easy to get a 70-71 iron 4V intake? Is this doable for a novice like me?  :-/

 
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mustang_maria73

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Agree with Don's recommendation.

also, you could swap the intake to a 70-71 iron 4V and nobody would know with the air cleaner in place. Skips the hokey adapter as well.
If I have to go with an adapter, is there one better than another?  Do you know what height/thickness I should get?  Thanks for the help!!

 
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I really liked the quickfuel carbs as well, but they look a little less original than a normal holley would. But still pretty accurate and the ones I had in the past were good little carbs.

 

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Hello all,

I bought the square bore Summit Racing® M2008 Series Carburetor SUM-M08750VS.  The Trans Dapt 2199 adapter doesn't work and it's really thick (15/16").  I haven't been able to find one that covers the emission groove fully.  See pic below with 2199 on top of intake.  A friend and his buddy suggested filling the groove with JB Weld.  I'm not sure I'm comfortable with this because I'm not very knowledgeable.  I see it being a problem if I want to swap back to my original carb. Your thoughts?  I guess there aren't any easy fixes for this. 😒

2199 on intake.jpg

 
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Put a 71 4V (M code) intake manifold on it. You'll still want to block off the exhaust heat transfer passages though. More info if you decide to go that route, please ask.

 

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Don,

Thanks, great idea!  Never would have thought of cutting my own (novice here).  I'll give it a shot.  Is there a special type of steel I should use?  Any other tips on doing this? Could I go thinner or do I need the thickness for durability?  Not sure I have that much height space left to the hood when everything is stacked. Already exchanged carb studs for taller ones. 

 
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Put a 71 4V (M code) intake manifold on it. You'll still want to block off the exhaust heat transfer passages though. More info if you decide to go that route, please ask.
I'll bite...what do you suggest is the best way to block off the exhaust heat passage?  Thanks.

 
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I'll bite...what do you suggest is the best way to block off the exhaust heat passage?  Thanks.
Two ways, well three if you just want to do it the quick way. First, the heat passage was intended to warm the Autolite 4300 carb and that was made for that purpose. If you're using a Holley or other newer carb, a base gasket with the metal insert (like a sandwich) will not be enough and carb overheating (and damage) may occur.

Without blocking off the heat passage, I was having trouble with fuel percolation from excessive heat under the carb. I had installed a Holley Street Avenger 670 (4v) as well as a 1/4" insulator gasket with the metal insert gasket underneath, but it was not enough. I also needed the spacer because the butterfly's on the Holley were catching on the intake bores. The first quick and easy attempt was to just tap and insert 5/16" set screws at the corners of the top under carb passage, see pic. Later I was still have percolation problems, so I pulled the intake and inserted a SS plate in each opening. As a former machinist (retired) it was easy for me to hand "mill" a ledge for the plate to sit on. I then used exhaust cement to seal it along with using a center punch to "stitch" the plate in place.  I also inserted a thin .020" thick SS piece over the corresponding holes in the heads as I was using the valley pan and thin gasket. That was overkill, but what the heck, double insurance. I'm not sure, but I believe you can get an intake gasket without the hole and then use a thin steel plate under it to block the exhaust holes and not use the valley pan. I think others have done it this way, so maybe more suggestions on the way.

IMG_2851_LI.jpg

IMG_0639_LI (3).jpg

 
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