I've heard you loose up to 5% power through a 150cc engine using flex headers over solid headers. The flex headers are alot easier to use than the solid headers, especially in a Carden where everything has to be perfect to line up. I cannot fathum 5% power being lost just from 5" of flex tubing. Shed some light on this myth please. I would think that since the bend is solid that it shouldn't loose power for the straight part of the header being flex tubing.

-Kelly

P.S. Here is a picuture of my header for referance.

Have you ever used the flex pipe on a 150? I have, and the engine continually blew the flex type pipe out. It was a pain in the butt so I went to a solid pipe. I know you probably can't do that, but you may run in to the same situation_bob

Hey Bob. What do you mean by blowing the flex pipe out? Was it breaking the weld loose or destructing the tubing itself? Were you using the KS headers like I have or a different brand? If worst comes to worst I will get the header kit from DA that involves piecing the tubing together. A friend of mine has been running the exact same headers I have for a long time and hasn't had any problem. the only thing I hear is about them leaking every once in a while, but we'll just have to see about that.

But what do you think about the flex tubing distrupting the exhaust flow?

-Kelly

Not sure what brand mine were as I got them from Aircraft International. They used to crack and leak right at the bend. I can't tell you much about flow or performance though. I got a few more rpm's out of the cans than I am the mufflers. I don't try to get the most out of my engine. I like to keep it on the safe side of rich and leave it at that. Hope that helps_bob

I have flex pipe on a ZDZ160 Champ/JMB cannisters and have been flying the plane all summer with no problems at all.

I got the flex pipe from RC Showcase. Part of why I may not be having any issues is that the cannisters are independently supported and the flex pipe is not used to support the front of the cannister. Also, the headers and flex pipe are two different pieces and are held in place with hose clamps.

I don't believe that I have lost any power using this flex pipe- For whatever it's worth, I get 5600-5700 with a Menz 32-10.

Dave