Airacobra

I have an older OS 61 long stroke and I have a Mac's header on this particular engine, but would like suggestions as to what Pipe I should use for this motor. It will be used for just all round sport flying, but wanted to try the engine on the pipe.

Bax

My Feedback: (11)

Just use a pipe intended for a .61-size engine turning about 12,000 RPM. We don't have a specific size to suggest. O.S. no longer makes a pipe for that size engine. A basic .61-pipe from Mac's ought to work nicely, once you get things properly tuned. They are not just bolt-on devices, and are certainly not "set and forget".