DIY installing N55 mid pipes on a N54...

[froop]

Originally Posted by JamJay

Installing N55 mids + BMWPE Resonator delete (PE axle-back previously fitted) on N54 135i.


Job for today?

Install these:



Onto this:



By removing this:



Cutting off this:



Sanding down these:





Making sure I didn't F-up the cuts like this:



Fitting like this:



Sounds like this:

I see you just went ahead and did it Jam.

Love the sound man. I think that I'm definitely going to have to go ahead and do this myself. I have gutted N54 mids as opposed to N55 mids but I like the sound of them at the moment.

I wonder if it's possible to get the BMWP exhaust and somehow modify it to make a quad exhaust...

[Cozy]

Originally Posted by froop

I see you just went ahead and did it Jam.

Love the sound man. I think that I'm definitely going to have to go ahead and do this myself. I have gutted N54 mids as opposed to N55 mids but I like the sound of them at the moment.

I wonder if it's possible to get the BMWP exhaust and somehow modify it to make a quad exhaust...

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.

[Cozy]

Oh, to add I now have a lovely turbo whine from the exhaust and performance has picked up. It's not massive, never was going to be but there's definitely more power and urgency low down and less restraint up top. I realise this can be a placebo so I took her to a road I know whell where I also know the character of the car like an extension of myself; results were that it bit hard and span up low down while reaching higher speed more quickly than I am used to on this particular stretch.

A very good mod on an N54

[froop]

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.

[Cozy]

That it would, has a lovely tone but I'd wait to pick up a cheap one before cutting it

The drone isn't really a biggy honestly, it's only there when you open the fully throttle up from 2k-ish RPM in a high gear, say 6th on a freeway just to bump up your speed. It's not there when crusing at any speed that I can tell although the exhaust note is louder over all.

I can now hear the pops and gurgles inside the car from time to time if the stereo is off, they are just crazy loud but as it's a coupe and well sound proofed you aren't stuck in the cabin with the exhaust tone like you would be in a hatchback, hence the drone isn't much at all either I guess. I was following one of those new McLaren 12C cars on Sunday, that was extremely loud on idle and gave some nice gurgles but my 1er made it look like a baby in that department, crackling all the way down a hill super loud...I think pedestrians were disappointed that it was my car and not the $$$$$$ supercar.

I'd say stick with your gutted midpipes, the only difference I could tell between N54 and N55 is that the N55 pipes seemed to be less bent. If you want to go louder then cut off that resonator (if that isn't gutted along with the cats); or louder still replace the axle-back with something noisy.

I wonder if an N55 car with PE & resonator delete would be as loud as what I've found?

[1ToBeOn2Wheels]

I've been meaning to order the N55 mids for my N54. Now thanks to you I think it's about time! I'm finally gonna get around to doing the golf tee mod too. The combination of the two should really beef up the exhaust to my liking. Like you, I'm not really interested in aftermarket midpipes or exhausts for now.

[dannypwr]

I did the n55 mid swap cel with P0050 and P0036 popped up , anyone else get this?

[darkrom]

Originally Posted by dannypwr

I did the n55 mid swap cel with P0050 and P0036 popped up , anyone else get this?

Did you beat up the rear O2 sensor during the install? Sounds like something is wrong with that rear O2 either way.

[Dackelone]

For cross reference - this might help some 1Addicts members...


DIY installing N55 mid pipes on a N54...
http://www.1addicts.com/forums/showt...=797160&page=5

[EldRick]

I went the opposite direction, and spliced a 135 mid-pipe resonator into my 1M in place of the 1M fake-resonator y-pipe.

Results are just what I wanted - the drone is greatly muted, while the character of the car isn't changed. The resonances at 2300 and 2700 rpm are greatly reduced - still there when the pedal is down, but much more civilized about it.

The car is quieter inside at idle and overall, but not a lot - it still sounds like a performance BMW, but not obnoxious about it, and it's much easier to hear the music. I guess it's for those of us who don't need to advertise.
6^)