Looking for blueprints for low side port holes on some older tillotson carburetors,341,342A,348E. Found one for a 348C in some of ec old stuff The holes under the soft plug are the ones I'm looking for
Jon brogden may be able to help you some. Drill patterns are the result of lots of time and effort, and as a result, most aren't just falling over themselves to give it away. I had a pattern saved in my PM's from Jon on the old site, but its long gone now.
I have a 340b that i"ve for 15 years blueprinted by ec himself that i ran on an open briggs that only has 2 small holes drilled in front of the throttle plate.I still run this carb now on a gx390 and it is awsome still.It does have a lot of milling done inside around the fulcrum area.It is set up for alcohol.I don't know what diameter the holes are but I also have a blueprinted one from ec also done by him and it has the same drilled holes.It is also milled around the fulcrum allso and the throttle shafts art cut really thin too.awsome carbs I'll never part with them.they run excellent on anything I put them on.