Hey Tom... What kind of battery power are you running on your GWS 350 D? The 12 x 6 prop seems like a lot of prop for that motor... Everyone's been saying how the GWS motors burn up really fast with the three cell LiPolly's... but mine didn't even get hot with the 10 x 4.7 prop.... and it had plenty of pull... I think I'd like to try the 11 x 4.7....