Hello, I'm building a 2-barrel intake for an otherwise stock later Slant. I found a low mileage Holley 2280 at the junkyard on a wrecked 318 Dodge conversion van and I've looked at old forums until my eyes are bloodshot trying to figure out what size jets the Slant version of 2280 came with. It doesn't help that most of these forums are nearly 20 years old and the links and pics in them are dead.. I did find on here that the 2280 uses "120-6 family" thread size, but not which ones? I've also found old posts of people saying you can just run the 318 one, but I'll probably just return the 2280 and look for a BBD variant if I can't re-jet the 2280 a little bit smaller.. Anyone know the correct jet size, or where to get them? Thanks..

https://photos.app.goo.gl/8v3eabUod5QDUDcm8

The difference isn't just this versus that jet; the airflow paths (venturi, etc) are sized differently in the Slant-6 carburetors versus the V8 ones. Also, there's the choke lever difference. The V8 jetting and airflow usually work fine on a Slant-6; unlike the automaker, you do not have to pass a federal emissions type-approval test in order for the car to be legal for first sale. Adapter to use a 273-313-318 two-barrel carburetor on a Slant-6 is described and shown here.

Also keep in mind the 2280 was not used as original equipment on Slant-6 engines; all factory 2bbl installations on Slant-6s were Carter BBD carburetors. Holley offered a couple of different versions of the 2280 for aftermarket replacement of the BBD.

Three other things:

• Low mileage since new (yum), or since "remanufactured" (yuck)?

• You mentioned in your DM to me that you got it off an ~'85. That would make it very likely a 6280, the feedback version of the 2280 – not suitable for use on a non-feedback application.

• You say you are making a 2bbl intake. That's cool. Make sure to set up the carburetor mount pad at the correct angle, as described here.

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.

It appears the 6280 is the one with the dildo sticking out of the side of it, mine doesn't have that, and it looks identical to one National has listed as being 86-87.. I think the odometer on the van was showing 80-something-k, I cant see any sign it's ever been removed. They had another one there that looks like it has been dipped in strong chemicals, the aluminum is turning powdery now.

If you are using an aftermarket electric choke, like a Carbs Only 1232, does it need to be in the factory chamber on the exhaust manifold, or can you move it around if needed? Basically do they need heat and 12v both?

My 87 van with its 318 had lean burn but definitely had the 2280 not the 6280.