Im glad you got things worked out.

When dealing with speed, there are a variety of factors that can cause problems. Im glad you got the fuel system issue worked out, that is always a killer.

Usually one would not have to back off quite that much. Usually about 1000 rpm down is audibly rich, but still with a 2 cycle sound. It is likely well rich, but still running at 14K.

On the QM engine, the ground peak is about 25K, we launch close to 22K, and in the air they hit about 28K.

What you described sounds like you are on the edge of the pipe tuning. If you requested "fast" setup from Dub, that is likely the case. You may never see 'peak' rpm on the ground, because the pipe only stages completely when the prop unloads. The prop can not unload on the ground, and you will see a false peak. That is how FAI engines are set up. The needle is a bit of an educated guess. Some of the really fast guys in QM and Q500 do the same thing these days when using very heavy pitch props... the muffler never stages, so the needle has to be set by feel, and a previously known needle position using a slightly smaller prop.

You may want to play around with a few different props. Some with give you better speed, some will prove to provide a more user friendly installation.

As the engine gets more time on it, it will accelerate up to RPM more easily, and you will notice you can lean it out a tad more. But, if you can keep it rich, that is always a good thing. Sometimes 'peak performance' is a less than 'max performance'. Keep the engine rich, live with a few MPH slower, and the engine will last and run like that for a long time.

Interesting note....... you mentioned you had to back off to 'very rich' at 13K rpm...... there are some "40"s out there that couldnt get a 8.8x9 to that RPM in the first place