OS 33GT Gasoline Engine for Pattern
Just received the 33cc from Tower. I bought into the hyperbole of its supposed ability to turn larger Pattern sized props at Pattern rpm. They cite props up to 20x10, and if that proves correct in trial, I have just the ticket.....20x10 MDK hybrid
I've been playing with the SAP 30cc and have had pretty good results overall. It isn't the most ideal set-up tho since the engine is a revver requiring high rpm to work properly. I've made it work in Pattern but it isn't the better set-up (YS170 for example)
The OS on paper seems to have better stuff for Pattern. Example: OS has increased the stroke of the popular 30cc engines (SAP and DLE are the best of their type out there), from 30mm to 32.5mm, while maintaining the bore at 36mm. I have not measured exhaust duration yet but it appears to be around 155 degrees, more in line with their 140 RX and 160FX 2 strokes. Should turn in the mid 7's comfortably, I hope, with something like an 18x12, and possibly in the low 7's with a 19x11 or 20x10
I plan to use a pipe on this engine (ES40G). The header will be the Hatori return to center originally intended for the 160FX. It has required reshaping the exhaust tube a bit and redrilling the exhasut flange to fit the 33GT exhaust port. Will build a soft mount for it this weekend and see if I can fly it Sunday weather permitting..
I'll post some snaps soon