MTK, Thanks for sharing all this information on the GT33. It seems that OSis on the right track with petrol. (you know how americans love stuff like GT something on an engine model!!)

Maybe Ioverlooked it in here somewhere, but any idea what your sound level is... about??

Ifeel that petrol will really evolve as soon as someone designs a carburetor four our needs. Walbro is great, for sure.. but Ithink its fairly clear there is much room for improvements. (for one, they are not designed for our R/C style servo linkage.. Iknow, thats a pettycomplaint.. but still)
OSseems to be the most likely to do this, if Iwas to imagine who would first. Ithink it only makes sense.

Or am Iwrong to think that the walbro is not the most perfect carb, that needs no improvements?? It seems that is the next leap for petrol RC engines.. a carb designed for for these r/c engines.

Anyways, thanks again for the reports!