Blackie,

Ref this thread: http://www.rcuniverse.com/showthread...804&forumid=57


The inference from that post is that without any ability of the muffler system to 'flex' there will be fatigue cracking from engine vibration of the muffler/header pipe. The thinking is that the flex pipe will have give and prevent fatigue cracks from it being too rigid. I don't buy into this. I've had many muffler systems over the years and the only cracking I've experienced in the exhaust system is from using a flex pipe. And in those cases the flex pipe is the part that fails. The OS header pipes are very robust and have a good wall thickness to prevent this.

The whole airframe will be fine. I didn't mean to cause you any undue worry. If you're using the stock engine mount provided or another isolation type engine mount things'll be fine.

hth

Jefff