In response to suggestions on a 4bbl for my flathead several members suggested a early GM carb. The problem I have is when going to swap meets is the sellers do not know what the carb was on. My question is how to recognize a suitable carb?
In response to suggestions on a 4bbl for my flathead several members suggested a early GM carb. The problem I have is when going to swap meets is the sellers do not know what the carb was on. My question is how to recognize a suitable carb?
We know that you can do a class A rebuild on these Teapots which would be a good bolt-on and about the correct size for a flathead,since most flathead cars had a manual choke can you set them up that way?I know I mentioned it before, but if you want a Holley teapot carb, I have some. If you're flathead has a loadomatic style distributor, Teapots have the correct vacuum signal for that.
We know that you can do a class A rebuild on these Teapots which would be a good bolt-on and about the correct size for a flathead,since most flathead cars had a manual choke can you set them up that way?
Take a gasket that fits on the intake carb surface with you to the swap meets and use this to assure that you get a carb that will bolt on. As an alternative, make a cardboard pattern to take with you. Any of the early carbs will work fine as all early engines were of relatively small CID; as long as the bolt pattern is correct. Keep in mind that you need a WCFB. If you need a picture, go to e-bay and print one of the myriads ones on there for sale. Mostly early GM V8 engines is where they were used.
Someone may jump in here and object that some Cadilacs were a little larger etc., but they are not so much bigger that you won't be able to just re-jet the carb to work just fine. The later, larger engines used larger CFM carbs and that is why they went to the larger bolt pattern carb bases. So stay with the small bolt pattern carb and you will be just fine.
Two things I don't understand are, why does he have to use a WCFB and not a Rochester, a WCFB or a Holley teapot, or for that matter a Stromberg 4 bbl.
Also, how does re-jetting an over sized carburetor make it flow less air ?
He doesn't have to, but his question was relative to early GM carbs and WCFB is the best choice there. I have a teapot on my flathead and it works and looks great. I recently rebuilt an early WCFB for a friend for use on his flathead; that also is a great choice. Late model carbs will also give great results if that is how one wants to go. Who are we to tell him what to use?
Re-jetting a carb will, of course, not make it flow less air on a given size engine as you well know. However, if one uses the same carb on different engines, at different atmospheric conditions, or with different camshafts or other equipment, it is necessary to check the jetting to assure proper fuel mixtures.
Something like this would be different, 2 Holley 94's on a 2x2 adapter on 4 barrel adapter. 4 Barrel adapter is drilled for different patterns. This went on a 289.