After I replaced the gaskets I adjusted the screws to 1.5 turns. Ill give that a try.
Any ideas to check fuel pressure other than a tee in the fuel line? Im looking for a brass tee to fit the fuel line and a vacuum gauge.
There is no set, exact number of turns That is right "off the bat". That is generally a good starting point to fine tune it from, with a tach and vacuum gauge once it is started and warmed up.
It's not a "open 'x' number of turns and forget it" deal. You put that carb on another engine and it will need (at least) slight adjustment from where it runs best on your engine.
On my 83 D250 (not a slant 6 but don't matter for the point of what I'm about to say) the original carb had plugs blocking the mixture screws when I got it. Upon the 1st tune up I drilled the plugs so I could access those mixture screws, and in order to get the best vacuum and tach reading I had to open both mixture screws "about" 3/4 turn each, from where they were set at the factory.
Ran much better after that. Where was it set initially? (How many turns from seated) Don't know, don't care. Where did it end up? Again don't know, don't care. It was where it needed to be to run it's best. I still have that carb even though the truck is gone (I eventually put a 4 bbl on it) but that original carb is a Holley 2280 very much like what you have.
