which is highest revving .61 nitro engine with Tuned pipe out there?
 

any one know what brand or combo engine + tuned pipe is available to get the most rpm

looking for .60 size engine to go on sundowner 50???

Jettfire 60?

OPS 60 Super SPP VAE, but maybe the sundowner explodes with this engine :D

Jett 56 with a Jett muffler. Proven combination that works well in that plane. Call Dub and tell him it is going in a Sundowner and he will send you the correct muffler adapter.

Agreed, the Jett 56 and Sundowner has been done and sorted out. I think it maxed out at about 130 mph, not blazing fast but maybe just about as much as the Sundowner can handle. If I was going to put one together for speed I would equip with a YS 70 and make the wings non-removable. Gluing the wings onto the wing tube would make for a much stronger airframe. FYI, high RPM doesn't always mean more speed. I have a Rossi .45 powered pylon airplane that I can prop to make 18K rpm but it flys much faster when propped to run 16K rpm.

The sundowner is a plane with a lot of drag. When you add weight you need a higher angle of attack to make it fly. A full sized 61 engine with full pipe, firewall, wing, and tail reinforcements will add 1.5-2 lbs more to this plane. you will be better of sticking a YS 70 FS in it and running high nitro