Mr67Stang

I had to click on RCU's banner for the Evo 60 NX when I saw it said it was in a 40 size case. I did some compairisons of the competition figuring the OS .55AX being the closest thing to it. Right now with Tower's discout the OS 55ax can be had for $5 less than the Evo 60nx and their numbers seem in line with eachother as far as props they spin (I never look at the so called power rating). Regular 60 size engines seam to be between 23 oz and up to 29 oz. This 60 nx comes in at 17.13 oz w/ the muffler and the OS 55ax weighs in at 18.52 oz w/ muffler. One ounce saved on the nose of a 40 size plane can be a huge savings of weight in the tail. Additionally the 60nx has a 60 size exhaust port matching that of the OS 61SF and FX engines meaning for those that would use a tuned pipe you can get the propper volume header and pipe for the cubic inches of the engine. The OS 55ax has an exhaust port of a .40 engine and you would be limited to 40 sized tuned pipes.

Well these are just some thoughts I had while compairing engines. If you can think of anything I'm missing here, let's hear it. I want the pro's and con's before I pull the trigger on getting one of these to make a 40 size big stick go fast. Conciderations specific to my decision are:

1) I already have an OS 55AX w/ Mac's tuned pipe (simple black one)
2) I also have a Mac's full tuned exhaust for the OS/TT 61's ($100 pipe and header)
3) The plane had a TT Pro 61 on it, which I still have, with the before mentioned pipe (just too heavy)
4) I would save 8 oz off the nose using the OS 55 ax
5) I would save 9 oz off the nose using the Evo 60 nx