Ihave several tuned piprs from my boats that i run. all are from modded 26cc zeonahs. what do you think that will do to a ryob. i think i can make it fit to the side of my new giant super sportster that will be here on monday. HMMMMMMMMMMMMMMMMMM

You mayl have a hard time using those pipes. Boat engines run tipical twice higher rpm than airplane engines.
Some pipes will be at quarter length though, so on second thought, it just might work.

Interesting thought Pe had on the quarter length. Let us know how it turns out.

If you can get [link=http://www.mh-aerotools.de/airfoils/javapipe_en.htm]This[/link] to run(java 1.4) you can check your boat tuned pipe and header lenght, against the exhaust port timing and rpm that you are targeting on your Ryobi