RE: evolution jett stream mufflers
Yeahbob, a badly set up (i.e. just bolt 'er on and see what happens) tuned pipe arrangement can easily be far more headache than a tuned muffler, deliver no more top end, have balky midrange and probably eat plugs and/or just give the owner fits. A properly set up pipe system can be a beautiful thing. I have a lot to learn about the whole affair still but I've paid a lot mroe attention to pipe setup since last season (seeing as I fly more of them now than ever) and lo and behold things make a lot more sense these days.
MJD