ORIGINAL: ChuckW
I had a SSE ARF with a Super Tigre .45 mounted int he stock position. It ran very well; no problems at all. I wouldn't hesitate to mount it just like the instructions show.
I also put the same engine mounted sideways in a kit built SSE. Maybe I built the kit lighter, maybe it was the streamlining from the cowl or maybe it was the carb position but this SSE was noticeably faster using the same prop and fuel. It also had a Macs muffler on this plane, maybe that was a factor too.
One problem both SSE's had is prop clearance with the stock gear. I was running 11" props. With the .55-AX you'll likely be running a 12". This means even less clearance. Order some taller, stronger gear from tntlandinggear.com or someplace similar. You'll be glad you did.
order schmorder... i do fabrication on fullsize aircraft for a living. you can bet that i already built me a nice 7075 T-6 gear with a bit more clearance for the bigger props the .55 will swing. (in fact i have become the local landing gear fabricator for my buddies for the most part) but thanks for the advice.
yel914, i saw pics of your plane in another thread when i was surfing around before making this post. looks hot! i might have to do something like that. but truth is i wanna fly this thing now! i have spent a lot of attention to detail so far (well it is an ARF, but what there is for me to assemble i have done my best on) so maybe i should get past the impatience and do it right like you suggested. we'll see. thanks for the advice and pics all.