Hello Been toiling away on my hot rod project and finally got to the point of running in the cam. I'm a little confused about my carburetor set up thought. It's an 8BA flathead with a knockoff Edelbrock 2x2 manifold. I have two Ford 8BA carburetors and I'm not sure if one is set up as a secondary. The carbs were built by Dave Tatum now deceased so I can't ask him. One carb has a small "s" stamped on the float bowl cover. Could that mean secondary? How would I tell if one is set up to be secondary or not? Both carbs are linked together currently and I think that's too much fuel for idle and low speed running. I found a progressive linkage set up at vintage speed but they said it won't work unless one carb is set up to be secondary. Any help appreciated!
Have you tried them yet? Not sure what would be set different in a secondary carburetor. For what it's worth I run two 625 cfm AFBs on my 409 with one to one linkage.
Secondary carb might not have a choke? My guess is they're probably the same. Don't worry about "too much fuel" from two carbs. Carbs are really good at providing fuel in the correct ratio for the amount of air the engine is pulling through them, which is mostly determined by how far you push down the "go" pedal. They're really versatile devices.
They appear identical from the outside. I've run it for 20 minutes to break in the cam about 2,000 rpm.
I've got an older version of that manifold for my 8 BA and figure to run both carbs in unison and not use them as primary or secondary. I'd have to dig out the flathead books off the shelf but am pretty sure that that intake is designed for the carbs to work together each feeding it's end of the engine rather than as primary and secondary.
^^^From what I know this is correct.^^^ Also you get in touch with Matt, at IronTrap Garage , Matt and Steve know there stuff and could be of some help.
Leave the straight linkage!!!!!!!!!!!!!! Your engine will not appreciate progressive linkage, and you won't either. Jon
For two carburetors you need each one to feed their end of the engine. Secondary applications are for three or more carburetors and usually the center is a primary while the front & rear wake up during acceleration.
I run dual four barrel Carters on a bone stock 383 big block dodge. Straight linkage, it is flawless, you would never know it’s not the stock two barrel driving it.
I did send an e-mail to Iron Trap and got a very prompt response. They advise this manifold is set up to run the two carbs in unison as others have indicated. Dial them in and let er rip. Thanks for the help!
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