Exhaust recommendations

[Varinn]

I'm picking up a stock m20b25 in a week or so to swap into my eta, there's currently no exhaust coming with it. I'll be installing a set of ebay headers, which I've seen installed and know are a good fit. Where do I go from there? I don't know the sizing needed for a stock b25 motor. I will be installing a flanged midpipe that will let me swap between the resonator(s) and cat(s)
should I stick to dual pipes or run a header back single.
O2 sensor before or after the crosspipe?
What brand of muffler for quiet but deep tone on a reasonable budget
What brand resonators?

I'm aiming for a quiet exhaust that flows reasonably well

[Morrison]

I would try to get the O2 sensor as far forward as possible and it is acceptable to feed it gasses from only one of the two banks of three. No need to wait for them to combine. As for a silencer, my personal opinion of best sound goes to the Sebring: http://www.ppcgb.com/Sebring-Exhaust...od10784/#10784 The cost with shipping to U.S. though would be $1078.24 so a little pricey.

This is part of a Euro-spec system, which means that the "rear section" will be a bit shorter than a U.S. version to accommodate their 3-piece system. But since you are already adding headers and a custom center section this shouldn't be an issue.

As for a resonator, you might look into getting the factory center section from a Euro cat-less system.