OK, kinda suspected you were running the stock CL intake.. The hole in the spray bar isn't big enough to allow the engine to ingest enough fuel in one gulp. Remove the insert if you are using it, drill the spray bar hole out with a #56 drill bit .046 and try to find or order a Thunder Tiger 11.3 X 6.5 prop.
You can try your fuel at first but also run a couple tanks of YS 20-20. It will probably be too fast but don't worry about that at this point. What you are looking for is consistency with no sagging, try putting the insert back in for a couple flights, if it's still too fast start restricting the intake choke area till you get the lap times you are comfortable with.
Of course this is assuming setting the needle on the rich side of full boat.. I've found I can set the needle easier by ear than with a tach, find the peak then start backing it off (richer) till it starts running rough, lean it out till the rough running stops and you should be in the ball park.
Let us know the results of the above, I am really interested to see if you have the same results we did.