I'm not sure if what I'm about the explain for a car exists - I haven't seen it so I doubt it does, but anyway.

Why isn't there a carb made that has "default" sized pilot fuel, pilot air, main, etc jets but has tapered seat screw that screws into and out of the jet bore. So the jets in the carb are replaceable (if you damage the seat, etc) but to tune the jets, rather than change the jet you can adjust the screw to regulate the flow through that particular jet.

That would making tuning carbs that much easier in one off situations, so for a manufacturer jets are the more viable option for mass production as once they size them its just a matter of using the same jet numbers in each carb.

I dont know about you guys, but I see it so much easier to just throw this hypothetical carby on any engine you want then use the screws to tune it (with out even taking it apart or off the car) and in a day you would easily have the car to a very drivable state that would only take a little bit more fine tuning.

So, just wondering - does such a carby exist; one that has basically externally adjustable jets?