Not sure which carb you have on there, but I had a '65 DeVille with a 429, and it had a Carter AFB carb on it. It's a simple carb to rebuild with a kit.
Edelbrock makes a copy of the AFB if you want to go for a new one. You could call Summit Racing if you decide on a new one, and they could advise you on which model would work.
Yeah Al, that's right. I had a new '66 Pontiac Tempest Sprint, 6 cyl OHC engine with a Q-jet. Had a hell of a time with that carb , and being new at the time, the dealer's guys didn't seen to know much more than I did !! So '66 sure could be a Q-jet. An exchange carb may be the way to go if DW isn't into rebuilding a carb.
If you care about it being original equipment rebuild it. You might want to have it professionally done. After many years the hole at the throttle linkage gets worn and vacuum leakage can occur. A good rebuild will include boring out this hole and installing a brass bushing. There are a few other areas, like casting plugs, that often fail causing other problems. You could call them design defects. The other thing to be ABSOLUTELY sure of is that you have the correct heatshield installed with the carb base gasket. The car will not run right without it. I just learned this on my 67 after 6 months of fiddling after a service tech threw mine away. Thought horrible things were wrong with my car. I didn't even know it was gone until I bought the service manual. Replaced it...and heaven! Hard to find to BTW. Let me know if you need one.
Now, if the carb is physically in pretty good shape you could just rebuild it your self. It is very easy. Just check to make sure that the base plate is not burnt through from a missing heat shield, that the bowl and other parts are not warped, and that various plugs have not popped out. If you rebuild it your self you should remove the old casting plugs and install new ones. A little epoxy over these is a good idea. If the base is burnt, the throttle shaft is excessively loose, or the major parts are warped, have a pro rebuild it. He can fix all of these things with out too much trouble.
In general, unless your building some sort of radical cadi motor stick to the original equipment. Qjets are great if one knows how they work. Some say nasty things about them but my opinion is its just because they don't understand them. Kind of like women. Personally, I think they are great and easy to tweak, as long as you install the heat shield. Qjets that is.
Incidentally, it is probably a Rochester could be a carter. Either way, they are pretty much exatly the same and the name on the side is irrelevant.
And another thing; If you stick with the original equipment, the vacuum lines will all match up, the heat riser bypass will be in the right spot and such. A new one may not fit. The base plate on your carb is different that most others. There is a channel that passes heat from the exhaust up through the intake manifold and if the base is not correct you have a big exhaust mess right on top of your engine. Hope this helps.
That's good advice I believe. I've fooled with a bunch of Q-jets, with quite a few mods for SB Chevys, and they work great. The faults are mostly widely known these days an are not difficult to fix. The heat shield story is typical of mechanics who "know it all" The shield wouldn't even be there if it wasn't necessary, and GM wouldn't spend the two bits to use it if it didn't need it.
Like I mentioned , my first go-around was a "66 Pontiac with a Q-jet, which became a learning curve for me and the dealer's mechanics