ORIGINAL: freakingfast

Do you still have the baffle, try and put it back in. That should help the mid range a bunch, but it will take away some top end rpm.

I use the ''KJ'' Uni-flow set up as my standard for for all my non-YS engines, works like a charm. This works like the standard Uni-flow except when the throttle is reduced the tank drops pressure almost instantly so the carb isn't suddenly too rich and helps keeps the fuel from surging into the muffler.

You need a OS bubble-less clunk, (other brands are cheaper,but don't work as well). A standard clunk (cut the line so it just doesn't reach the other). Two check valves (light spring), keep these closer to the tank than the muffler. A fuel safe ''T''. The pink vent line goes to the forward top of the tank as usual. Fill and drain point is between the filter and tank.
If the plane has sat for a few months the check valves can stick, just disconnect from the muffler and connect that line to filler pump to push than pull just a few turns, than reconnect to muffler.

Tip: cut a short length of fuel line and use needle nose pliers to stretch it around the outside of your lines to help your lines from slipping off tubes and fittings. Use a sharp blade to cut fuel lines, never scissors because the pinching action of scissors can make the tube split lengthwise later on.

A picture is worth a thousand words, here's a mock up: