Progressive 2bbl

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2 Darts

2 Darts

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Just picked up a '73 /6 that needs a little work to be a driver. Wonder if anyone has ever tried a progressive 2 bbl (like a 4 bbl split length wise, so there would be single primary and single secondary venturis) on a 2 bbl /6 manifold.
Phord used a carb like this on some of their 4 bangers. Don't know if one would have enough flow for the Mopar.
 
Used 32/36 Webers on a couple old Jeep 258's. They were progressive and worked well. Pretty much same bolt pattern as a BBD.

As long as you have a common plenum you can get by with it. Don't even think about it on a 318.
 
Don't see why not. The Holley/Weber uses stock Holley jets for air bleeds and stoveboltengineering.com has adapters for the one barrel manifold to mount them. They were available on engines in the 2-2.5 liter range so you should be able to jet them for 3.7 liters. If you want to change the manifold get an Offy 2X1 barrel and use carbs from an Escort. I know that works since it is what I have on my 225. Got the carbs, linkage, adapters, and air cleaners from stovebolt for less than $300. Now if I could only find an exhaust, without dealing with Clifford, so it could poop as well as it eats.
 
A lot of reports on the progressive 2 BBL have be great. MPG is really the best with this set up if tuned properly. Progressive 2 BBLs are sought after so you can sell it if you dont like it.
Frank
 
Thanks for the hint on AMC, Chief. Went digging around and found 2 progressive 2bbls they used from the mid to late 70s. With AMC I6 CID close to Mopar, these are likely set up adequately for the 225 /6. The carbs are the Holley 5210 and the Motocraft 5200.

The Motorcraft comes with a caveat. All threads are metric. The early bolt heads were also metric. Later bolt heads used SAE sizing.

Thanks guys. Now I start collecting parts.
 
Thanks for the thought but I've thought about that. For nearly $300 I think you should get more than a manifold and a hacked up stock exhaust. And that is after a nice long wait. Unless you want to spend $425 for 2 manifolds with no provision for carb heat and grind the rear one to fit. If I could find header flanges the right thickness I would make my own.
 
The 32/36 Weber is rated at 300 cfm according all sources that I consulted that would provide a cfm rating. Found several Jeep guys who had 258 CID I-6s that had swapped the Weber for the factory BBD. All report that fuel economy and performance is better.
 
hey,
i'm using two of the stovebolt progressive 2bbl carbs (the ford escort carbs) on a 230 ci chevy inline 6 and i love them. throttle response is MUCH crisper than the old setup (2 1bbl carters) and mileage and top end power is also much better, but it lost a little bit of low end torque. i'm also backing this engine with a 2800 stall converter (its what i had at the time) but it still runs like stink. setting up linkage was a bit of a custom job requireing a bit of fab work but it works good. it has since been converted to a much simpler cable setup after this pic was taken...
ENGINE2.jpg

ENGINE1.jpg

-tim
 
I have used the progressive Webers on VW air-cooled engines and 2.2L Mopar 4 cyl. The stock plastic foam float does not seem to work well with the modern gasoline. After a couple days the floats can sink. Years ago brass floats were available. Make sure there are no snags in the manifold at the carb mount. An air cleaner spacer 1-2" high above the carb, helps the flow. Manifold heat is important for cold temperatures.
When correctly tuned, the power, response, and economy are great!
 
Very Cool, Optik. That's twice the capacity I'm looking for.
Took a look at a dismantled Super 6 this weekend. The throttle and kickdown linkages for the 2 bbl are not the same as for the 1 bbl. The good news is that the Super 6 intake is basically an open plenum under the carb. There is a small divider that I think I'll grind out to make it a bit more free flowing. The good thing about the Super 6 intake is that it does have the heat and EGR provisions my 73 needs.
 
Wrote to Redline/Weber concerning swap. They are steering me towards the DGAS which is a "synchronous two-barrel". They say is has more of a "Wow factor". At $3.75/gal here at the edge of the world, I'm not looking for a whole lot of "Wow". WTH? Isn't a BBD a synchronous 2bbl? Can someone explain?
 
I went from a BBD on a factory super six setup to a Weber 32/36 DGEV?, anyway it had an electric choke. This was in my 74 Dart with the engine and accesories from a 79 Aspen. Gas mileage was a bit better. The key thing is to learn at what point the second barrel opens on the 32/36. It is not vacuum operated, it is mechanical. There are factors to consider when tuning such as rear gearing, adjusting the kickdown, jetting, etc. Also, I got rid of all of the emissions crapola. But the Weber is VERY easy to tune. One more thing, if you go with the Weber, you will need to swap over to a cable operated kickdown and get a longer throttle cable. And do some minor modification to link it all up. The levers on the Weber are not on the same side as the BBD.

Brian
 
One more thing about the Weber swap, I used the adaptor mounting plates from Weber to the factory manifold (2bbl). This raised the carb height by a couple inches. VERY close clearance with the air cleaner lid to the hood.

Brian
 
Optik said:
hey,
i'm using two of the stovebolt progressive 2bbl carbs (the ford escort carbs) on a 230 ci chevy inline 6 and i love them. throttle response is MUCH crisper than the old setup (2 1bbl carters) and mileage and top end power is also much better, but it lost a little bit of low end torque. i'm also backing this engine with a 2800 stall converter (its what i had at the time) but it still runs like stink. setting up linkage was a bit of a custom job requireing a bit of fab work but it works good. it has since been converted to a much simpler cable setup after this pic was taken...
ENGINE2.jpg

ENGINE1.jpg

-tim[/quote

is that 230 in an early model chevy van?
Click to expand...
 
That's what I thought, Chief. I can get cheaper "WOW" out of 350 cfm Holley.

Thanks Brian. That's what I'm looking for. Good answer backed by experience.

Steve
 
Looks like I'm gonna build a setup not unlike Optik has on that Chevy. I've got two progressive 2bbls from 1.6 escorts(new) with electric chokes for $150...shipped!:cheers: And I'm working on getting the Offy 2x1 manifold, and I'm going to call stovebolt tomorrow for a pair of carb adapters and some linkage. Looks like all that'll be left is some sort of air cleaner or two. Any suggestions? I'm really digging the ribbed ovals. Guess I'll need one of those Offy valve covers to finish it all off. And those adapters look like they could easily house a pair of spray bars for nitrous, or anything else that one might want to spray into their fuel/air mixture.
 
Hey Tim,
I noticed the old wooden clothespin on the hard line. I've heard of this to keep the line cool. Can you explain it at all? I just couldn't see how it could work. Thanks,Dan
 
I just got off the phone finalizing my order from Langdon's Stovebolt, and I learned quite a bit in the short time I was conversing with Mr. Langdon. To say the least, the man knows his stuff. With any luck, his parts and what I learned today will make for a sweet intake setup for my slant. I give the experience two thumbs up.
 
So, just out of curiosity, does $450 or so sound bad for that offy 5041, 2 new holley 1675 2bbls, 2 2bbl-1bbl adapters, and a linkage kit for the carbs? I figure hard lines for the hookups and the kickdown will put the cost at about $510-$520 for the whole conversion.
 
Just for grins, I looked around. One vendor was selling the manifold with install kit for over $400. Seems to me you have a good deal sitting in front of you.
 
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