This thread has been quiet for a while. Thought I'd post an update on my latest upgrade. I decided that a little more power was needed, particularly at takeoff so I removed the Saito 1.70 radial I flew with last season and replaced it with an Enya VT-2.40 v-twin with McDaniel/SonicTronics onboard ignition and Keleo Creations exhaust. It's got unbelievable power and swings a 20 x 8 prop at 7,100 rpm. The sound of the big V-twin is awesome. I'm hoping to test fly it next weekend. Here's a link to a short video:
http://www.rcuvideos.com/item/VXQYB27VYMQD1RSH
A few pictures: