Originally Posted by JamJay
Yeah, I kind of just thought that if I didn't like it, it would be easy to just bolt on the resonator in place of the Y-Pipe. Right now it's hella loud, cold start makes my brain vibrate and at around 2-2.5k RPM when pushing on it and opening up the throttle wide from lower in the rev-range (say 1500RPM) to get up some speed you get some cabin resonance. Cruising around town sounds no different really, part throttle sounds deep kind of like the ZHP E46 330Ci but a little louder, warm idle is deeper but not louder. Full throttle is where it's at, it screams a high pitched tone, sounds very high performing rather than ricey.
I cannot imagine this setup with catless DP's, I'd probably go as far as saying "don't do it" but instead get some Berk or Maddad style mids to tame it down, I don't even think the N55 resonator would be man enough. What I've found is that I get a little rasp sound when initially starting up, this is not vibration but what I believe is a characteristic of totally new, polished and coated pipe being bedded in...you know how new exhausts sound, a little tinny and less deep. The rasp is present only then and goes away when warm idling, partially remains on cold idling but is not present when driving or punching on it either. I imagine that with a fully catless car this rasp couldn't be muted and would probably extend to accelerating as well. If I ever go catless I'll be selling on the N55 mids (rewelded) and going for resonated mid-pipes. I guess you probably know this all anyway with gutted N54 mids, that must be loud also.
I'm giving it a few hundred miles for this pipe to soot up, it already sounds deeper after a good trip yesterday but it needs to come down a little more; not necessarily in volume but to lose a little of the raspy buzz you get on start up; then it's perfect.
As for converting a PE , I don't see why not. The Eisenmann quud uses a similar muffler right? I'm sure the muffler on the PE could be adapted the same.
Thanks for that. I reckon the PE as a quad would be awesome.
By the way, to reduce the drone, you could possibly consider just getting some pipe cut out and resonators welded in. I had a friend do this and he said it helped a lot. He has catless DPs and the N55 midpipes with stock exhaust (with 'golf tee mod'). It might be cheaper than buying a set of berk mids but I guess it would affect re-saleability if that's of concern.
I have stock DPs and stock axleback with the 'golf tee' mod. It's pretty damn loud already at cold start and when driving haha. I think that the new PROcede maps (which set the default wastegate position to 50% rather than 90% closed) might have something to do with it though. If I go catless DPs and/or the PE exhaust I'll probably go down the route of removing the gutted cats altogether and welding in resonators. I still have my stock N54 pipes lying around. I bought the gutted N54 pipes for $250 shipped.