Engine for sig somethin extra
 

I'm thinking of putting the Tower .75 engine in my second SSE. In my first one I had the OS 50 sx, and I liked it okay but now that engine is in my twist. The .75 seems like the same engine as the .61 except bored out which means same dimensions but lighter weight. What do you guys think? Will it even fit? From mounting flange to the other mounting flange the .75 is 8mm wider then most 46 size engines.

I'm building this from a kit, unlike the first one, and I've heard some guys say that it comes out fairly tail heavy so, if I need to add weight to the front I'd prefer to do it in the form of more engine weight.

RE: Engine for sig somethin extra
 

Don't count on it being THAT much lighter. Bored out means larger piston, probably larger conrod, maybe larger crank, so on. So, that weight tends to come right back in other forms. However, it shouldn't be much heavier (if at all) than the .61, if in fact it is a bored out .61.

I've seen guys fly them with saito .72's and .82's, so I don't see why it wouldn't fit! Needs to be propped down, probably--like a 14 X 4, or 13 X 4 (not sure which would be best for this particular engine), but I wouldn't go over a 4 inch pitched prop because of flutter problems and so on.

Good luck..
Hope this helped.

RE: Engine for sig somethin extra
 

The weight is less according to tower by about an once if I remeber correctly. The dimensions are otherwise the same. I think I will give the 75 a shot and see what happens.

RE: Engine for sig somethin extra
 

The Somethin Extra with the Tower 75 is great. It sure livens up this little plane.