RE: Showtime 4D and Evo 26 gasser??
Gentlemen,
I'm going to help you solve this one, because I just can't resist. I have a Showtime and I use a BCMA 26cc gas engine in it. I did have to cut the cowl more than I would have liked due to the side carb and side-mount muffler, but the airplane performs fantastic!
Plenty of power, great handling, no complaints here. I think the BCMA 26cc is a little lighter, (38 oz. with muffler and ignition) than the Evolution 26cc, but probably not much. It is rated at 12 lbs. of thrust. Both of these figures are from the website, I have not weighed the plane is it is.
I have several flights and have noticed no problems with the airframe as a result of the engine. I have, on a side note, had the landing gear plate fail and break off, causing extensive damage to the SFG's. The plate was really not well reinforced, but I suppose that belongs in a different thread altogether.
Anyway, I hope that helps. It depends, I think, on what weight your gas set-up ends up being. You do save a little bit of RTF weight since you don't need as large of a gas tank as with nitro, but I think that is probably negligible in the end.
-Pat