I have a mercruiser 233 and have been looking into replacing the old rochester 17056197 carburetor. This is a 2 bbl carb, and fits directly onto the manifold. In looking at new replacements, there are 2 questions that came up. First, should I try to use a 2 bbl or 4 bbl carb? Carbs I am considering are the Holley 500cfm 2bbl 80402-1, and in 4bbl the 600 cfm holley 80319-1 and the 600 cfm Edelbrock 1409.<br /><br />Second, which ones will fit?<br />After consulting a few parts sales sites, I am a little confused on what parts will fit. It seems like none will fit directly on: some require adapter plates, and others require a new manifold, then possibly linkages. The bigest problem I am running into here is which manifolds or adapter plates will fit... I was told this engine is a merc 233 / ford 351M. however, some of the sales folks I have talked to say the merc 233 is a 351W. How can I tell which it is? The engine serial number tags are not legible. Any other comments on other parts required would be appreciated.
