disapoining et

The 1:1 linkage having all 4 throttle blades open at the same time is a bad idea as well. That can't be changed to a progressive set up because of the squirter location/function. If it has been altered to progressive the carb is now junk without new linkage.

Carb is the first item that needs to be gone from your set up IMO.

It's the wrong carb for this use.