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Would a Holley 07448, 350 cfm with .031 pump work on a 1950 GMC 270 with 2 barrel military 302 intake, also has Fenton dual exhaust manifolds? Also, any suggestions for converting the throttle to cable or linkages to use. Thanks. Jim

It wouldn't be a bolt on, you would have to make an adapter and also make up throttle connections.

We ran the 7448 on 350 Chevy round track race engines, at speeds up to about 6200 RPM, so it's got more than enough volume capacity. The 2 barrel intake should eliminate the problem of restricted mixture flow that happens when that carb is used on a Chevy 1 barrel manifold. Use a fairly low vacuum power valve, like one in the 6-8 inches of mercury range to avoid getting too rich when the throttle is opened quickly. Holley has a wide range of main jet sizes so calibrating the mixture for high-vacuum cruise shouldn't be a problem.
Jerry

What 2 barrel carburetor would be a direct bolt in for this intake. Bolt spacing is 1-7/8 by 3-1/4. Military 302 intake.

I believe the original equipment carb was a Zenith. Not sure of the model number, but we used them on our flathead Ford race engines back in the early 1950's, highly modified to run on an alcohol/peroxide mixture. We outran engines running 3 Stromberg 97's with that one carb.

Carb King can probably get a lot more specific about the OEM carb- - - -I'm pretty sure they're scarce and very expensive now.

Edit: Search Ebay for "2 barrel Zenith Carburetor". There are several carbs listed with those base bolt measurements. None appear to be for a 270 GMC, though.
Jerry

Thanks Hotrod. Looked on eBay and had seen several with that bolt pattern. Was hoping to get something that would be jetted, sized close to what I needed, and bolt to intake. I can fab the linkage or cable. I've got it running on a 2 barrel TBI but not running well yet. Don't have a lot of time and needed to get it running so I can move it while building my house. Can mess with the TBI later. Had looked at some Stromberg ww carbs that were supposed to have been used as well.

270 GMC engines used 1 bbl Zenith Carbs.

You can use reducer rings to run a 302 intake ("big port") which has a 3 bolt Stromberg/Holley base pattern and that will get you a 2 bbl Stromberg or Holley that was stock on the 302, or, you cam get a grinder and hog out the mouth of that 4 bolt military intake you have and make an adapter as suggested and run a 4 bbl carb of your choosing. The only 2 bbl bolt on will have to be using the stock intake from a 302. I'm running a Holley AA1 2 bbl on that intake and so is one other person I know on his 270 engine.

Check the original post- - - -he's running a military intake, and some of the 270 milsurp engines definitely ran a 2 bbl. They were cheap and plentiful back in the early 1950's, and a single Zenith truck carb would outperform multiple Strombergs on the flathead Ford V8's. Some even had removable venturis, and Dad would set them up in a lathe and bore/reshape them for added airflow. The competition couldn't understand why all they could see was the rear bumper of that little single-carb rig!
Jerry

This is the intake. It has 4 bolt base with 1-7/8 by3-1/4 bolt pattern. I believe they used 2 barrel Rochester 2 GCs or 2 barrel Stromberg carbs on this manifold. Just reading on Internet various sites is why I think that. Thanks. Jim. Also my 270 has "H" head with big intake ports, no reducers required for intake. Thanks. Jim

Oops.
http://s894.photobucket.com/user/ea...age_zpse020553a.jpg.html?sort=3&o=22

Well, just purchased a Rochester 2 GC off 67-72 Chevy forum. Was for a 67 Chevy C20 with 283. Hopes this is close to right for my 270. Let me know what you think about it. Thanks. Jim

I have a holley 350 on my 261 engine adapted to the 1bbl intake. It sounds pretty good but haven't got to drive it down the road under a load. was also going to do the hei convertion in hopes they worked good together but have since changed plans on my drive train and quit messing with it.

Waiting on a retuned TBI chip to get it running right with the TBI. Then I'll go get the exhaust put on it. If I can't get the TBI working right with new chip, I'll be putting the rebuilt Rochester 2g I have on it. Jim