I have a 250 blower with a 1050, It has a carb spacer to go from the 4150 to the 4500 series carb there is a noticable difference in between the two flanges. By looking at it, where the adapter bolts to the flange on the blower in your opinion is there anything to gain if I open this area up or is it better to leave it alone?
Thanks EWB

FYI The bolt pattern on that adapter is the same as any 6-71

I have seen those adapters modified for the domninator.

Are all four throttle plates unrestricted when they open??

If they are and the size of the bores are clear, I really don't see any advantage to opening the adapter any.