Hello, I am newbie here, but if I might, I'd share my experience with carbs on my Evo. Ev-27 cam, points, '84 FXWG headers and SE slash cuts. I put a 42mm RevTech Accelator I on it, replacing the stock 38mm Kien butterfly. Holy poo-poo! That thing must have dropped a 1/2 gallon of gas down the holes every timeI got on it. At low RPM it would stagger the engine, and then knock you off the seat when it lite up. However, at road speed RPM it would launch like a fighter plane.
I put a 38mm shorty E on and everything works at all speeds as it should. ZOOOOOOM!
I think that more important that what carb, what size or who made it, the key is what is working with it.