Tower J3 Cub engine choice
 

I am putting together a Tower J3 Cub and I have several engine choice's and I am wondering what you would choose
os fs 70
asp fs 70
evolution 10cc (.60) gas
TT 46
all of these are new and I would like some opinions on what to use the gas engine is really what I am thinking about using because there is plenty of room for all the other stuff that goes with it and I have the pitts muffler for it (bisson) my only concern's are will I get enough muffler pressure and do I need it will it be way to loud and has anyone thought about a spark arrestor because the grass is kind of dry here please don't laugh I don't want to start a fire if I crash.
Thank You for any helpful reply's Greg

I would use the OS four stroke. You will love the sound as it is circling your field on a nice summer evening

The O.S. 70 four stroke is the best choice. Period!