Thanks for all help.
I'm planning to use this engine for sure on a scale in the future, probably a WW2 bird, but not sure which one yet. Meanwhile, I'm going to use in my 40 size trainner that need an engine since I returned the evo 46 that was on it.
I already use a RCV on my piper cub and will need another one for my tucano.

Based on my plans for it, any changes to what you guys recommend for the .50 range? The Magnum .61 and Saito .56 are both under 200 but the YS .63 is $288[X(]

By the way, what you suggest for a .90 size 4 stroke (for the Tucano). I was thinking about the new RCV91CD that is still to be launched but I'm not sure when and may never happen.Below some research I did for .90 range.

RCV-- RCV91CD--$229.00
OS-- FS91-II-- $229.99
Thunder-- F-91S-- $189.99
Magnum-- XL91RFS-- $189.99
Saito-- FA91S-- $239.99


Nilo