[Lukesportsman]

Well written by both John and Bill.

"The Flowmaster is a particularly good design becuse if the inlets are properly done the collector sees it as atmosphere, all the glass pack designs are seen as extensions of the collector and will therefore affect the acoustic tuning of the pipes sometimes for the better sometimes for the worse.

For the Flowmaster to be seen as atmosphere the pipe needs to penetrate the inlet stub". BILL

The difference between a baffle race muffler and a glass pack muffler is one of those areas that MANY racers of MANY brands never consider or appreciate. To each their own and sometimes due to collector length there certainly are circumstances where packed mufflers might work, but they are NOT interchangeable.