2 barrel carb - barking up the wrong tree?

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SirRobyn0

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@Rusty Nail I'm sure you already know this but in the 70's literally about million Dodge vans were built, most of them rolled with the 360 - 2 barrel Holley. A good number of them found there way into chassis where they became class C RV's or truck bodies. I'm not saying that a 2 or 4 barrel is better or worse, rather I just think it's a different way of thinking. I had a 77 MH with the 360 - 2 barrel, I removed it installed a 4 barrel, and eventually went back to the 2 barrel. The reasons being was I had issues with the manifold I choose to run and the metal kick down linkage for the 727. I could not tell a performance or fuel economy difference so I went back to the 2 barrel.

In my opinion a 4 barrel sized and tuned correctly has the ability to likely get better MPG than a 2 barrel in a rig driven with a light foot. Not in an RV though. IDK, I'm not saying anyone is right or wrong just relaying my thoughts and experiences.
 

75gmck25

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Full disclosure - I’m using an 80’s vintage Quadrajet that I rebuilt with a kit from Cliff Ruggles. Buying a Quadrajet for a non-stock engine is like buying a toolkit (or maybe Legos) that has to be configured to work with your application. As soon as you deviate from the stock application for that carburetor you have lots of choice and lots of opportunity to get it wrong. Quadrajets are not “one size fits all”, which is one reason people fight with them so much.

If I was starting out looking at choices, I think the simplest and most effective solution is a dual plane 4 barrel intake and an Edelbrock AVS2 carburetor. The AVS2 has several improvements over the old 1406, and the price is almost the same. Edelbrock tuning is also relatively simple (rods, jets, springs), and you might even be able to run it right out of the box.
 

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I have seen Webers on V6's and small V8's in boats. I used to convert old D-Jet injected vehicles to Webers (4's and 6's).

The 400 SBC I bought 30 yrs ago came out of a 60k '72 Caprice with a factory 2 bbl carb on it - (Rochester / Holly? - dunno) . I bronzed it and set it next to my baby shoes.
 

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So after some more investigation and member's advice about single vs dual plate manifolds, I realize I was miss guided. So what I'm considering now is finding a TBI manifold and having an adaptor made for the 2 barrel with a nice smooth transition from the 38mm. Seem reasonable?
Also this is a work truck driven short distances to haul around 4x8 sheets of plywood from a lumber yard to my shop, so I'm not concerned with mileage or high RPMs.
Elevations between 5000 and 6000'. No reason to worry about cold weather stating, it's sunny all the time here ;-)
 

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