i figured it was a butterfly issue. After all these carbs are NOT MENT TO HAVE AIR RUSHING OVER THEM. If you add a little turbulance then i multiplies the problem. Plus the 'displacement' (if you will) that the screw gives while at full throttle could closely measure a 3/4 open butterfly if you see what i am saying.

I know that those RPM's sound low. . . they probibly are and i am going to try a few different props to see what happens. But there are a few aeronotical thoughts in that as well when dealing with a prop on the ground in the B.S. measurement of 'static thust' vs. a prop 'unloading' in the air. I am not discrediting those of us that get all hung up on ground RPM, but the fact is that has almost nothing to do with how it flies a plane. (i said almost)

Ralph is correct about the muffler i am sure, and i would like a new one as well a few props to try.

I might use a little throttle curve just for my own thumb to brain link-up. But i think i might 'rig' it with some throttle switching. i.e. thro1 high idle (start mode) ... thro 2 low idle with thro curve adjustments ... thro 3 low idle with NO thro curve. That way i can continue to switch and monitor thru' the summer to make sure when it seats a little more.

another note...

I might not be the best mechanic with these engines, but i am no dolt in the schoolastics of aerodynamics and aerospace science. i can assure you guys that while 'static thrust' and max ground RPM do hold a place in this hobby/sprot it will not always tell you how your bird will fly with its power-system in the air. That is not 30 years of experiance, thats about 1200 years of hard physics

i honestly expect a few Forum a#$ whoopings for that statement. Who knows maybe i can Gallaleo (spelling?) myself in the forum world!!!!

anyway, thanks for the expert advice guys. . .thats why i am here.