Whats the Diff between a marine carb and an automtive carb? Just curious-Thanks

The main dif is that the bowl vent is shaped like an upside down j , rather than straight up. They can be converted.

A lot of them also have a provision for the fuel pump "puke" tube that will stall the engine if the fuel pump diaphragm breaks.

Well, if you ignore the gaping 3/8" tube for the master cylinder vacuum brake assist, the vacuum timing advance port, vacuum this and vent that, they're pretty much the same.

I swapped out the stock 2bbl Merc Rochester for a used QJet I had left over from a '69 Chevelle and had to epoxy fill all of the vacuum tubes (throw some in any cup plugs, too), and play with the power and main rods + jets.

A trick to avoid "bog" when doing evasive high-'G' moves with a Qjet, is to cut a piece of gasket material to sit over the main metering rod cavity - overlap the stock gasket and then cut through both.
Temporarily assemble the carb, and gently squeeze the rods throught the new gasket to provide a real nice seal. Re + Re with the new gasket butt up against the stock.
This will prevent the fule in hte bowl from splashing up and bogging the cubes when you need 'em the most.

Gotta love the QJet and Detroit Iron....

About 150 dollars!!