CARBURETOR

Soulmate

First, welcome
second, this is kind of an engine question and belongs in the engine thread. The "new" thread is news that the administrator of the site puts out.
Third, I wish I could say for sure on your carb, but I cant. All the ford 351s (the primary nautique engine) used the holley 4160 4 bbl, 450 cfm. I cant say for sure that they put the same one on the smaller 302, but I am guessing probably. Why dont you know, new boat with no carb or old boat with aftermarket carb? Anyway, yes you definitely need a marine carb for fire/explosion safety reasons, different seals and "j-tubes" to return fuel to the barrels. I also have a 76 tique but 1. its a chevy and 2. it has an after market Edelbrock, which I would highly recommend (model 1409, 600 cfm)
Fourth: about the porpoising. Its a fast little hull and as far as I know they pretty much all porpoise, but hopefully not at speeds under 40. So that is above ski speeds and just about above barefoot speeds, so it shouldnt affect your use too much, although mine does porpoise at footin' speeds sometimes. There really isnt much you can do about it unless you want to mess with trim tabs but not too many people do that on these inboards. Again, welcome, hopefully someone who knows for sure will let you know on the carb.