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.

[mblaucoupe135]

This should work on the 335is exhaust too right?

And I'm just curious why the n55 doesn't have secondary cats like the n54 does?

[Cozy]

Is the 335is N54?

If so I can't see why sticking N55 335i mids on would be an issue, they must follow the same path.

The N55 is a more fuel efficient engine with one large cat in the downpipe. The N54 is fairly polluting and as a consequence has four mid-sized cats to controll its emmissions.

[mblaucoupe135]

Originally Posted by Cozy

Is the 335is N54?

If so I can't see why sticking N55 335i mids on would be an issue, they must follow the same path.

The N55 is a more fuel efficient engine with one large cat in the downpipe. The N54 is fairly polluting and as a consequence has four mid-sized cats to controll its emmissions.

Yeah the 335is has an n54. And that's interesting that the n54 pollutes the air so much more as it is really only about a 5 to 6 year old engine. However i guess technology changes quite rapidly these days.

[jsaw421]

Originally Posted by Dackelone

Now IF only I had a BMW PE with some pops and gargling, I'd be a happy camper.

With the insight you provide to our community, I'd be happy to chip in for you to purchase PE.

Any others?

[phillye30fanboy]

smokin mids, my *****

[mpiligrim]

That should work for 1M too, am I right? ...

[Marco@McKennaPerformance]

Great write-up sir. We've had many inquire regarding the N55 mid pipe retrofit; I'll be sending them here for an in-depth instructional!

I saw that you mentioned the mid pipe is currently going for approx. $333. Just an FYI to all members, our parts dept sells it for $243. Hopefully the savings allows more to enjoy this exhaust retrofit!

Originally Posted by Dackelone

#18307599743 ~$333

[Cozy]

That's an incredible price. For tuning the N54/N55, there is no better place than the USA; we have nothing in the U.K and what we do have is massively overpriced.

[Dackelone]

Originally Posted by Marco@McKennaPerformance

Great write-up sir. We've had many inquire regarding the N55 mid pipe retrofit; I'll be sending them here for an in-depth instructional!

I saw that you mentioned the mid pipe is currently going for approx. $333. Just an FYI to all members, our parts dept sells it for $243. Hopefully the savings allows more to enjoy this exhaust retrofit!

That is an amazing price! I wish I paid so little for mine. But still the N55 mid pipe was well worth mod - it to me. Thanks for supporting us 1Addicts.

[Dackelone]

Originally Posted by mpiligrim

That should work for 1M too, am I right? ...

Yes, it will work for the 1M. The 1M has higher flow main and secondary cats... but still getting rid of the secondary cats will free up the exhaust flow.


I believe the N55 mids also solve the 1M's exhaust drone. The reason is the 1M has a "fake" resonator that is hollow(no fiberglass packing/sound deadening) while the N55's resonator is functional. See my link bellow...


found out something interesting about the 1M exhaust...
http://www.1addicts.com/forums/showthread.php?t=779462

[josh135]

Nice write up! Sounds good as well.

[KingOfJericho]

Originally Posted by Marco@McKennaPerformance

Great write-up sir. We've had many inquire regarding the N55 mid pipe retrofit; I'll be sending them here for an in-depth instructional!

I saw that you mentioned the mid pipe is currently going for approx. $333. Just an FYI to all members, our parts dept sells it for $243. Hopefully the savings allows more to enjoy this exhaust retrofit!

I just called your parts department and was given a price of $403.20 and they do not have them in stock. The website does say $243 but the guy said that must be incorrect.

[Freon]

Thanks for the writeup, Dack! I think I may go this route for midpipes to finish my exhaust.

[Marco@McKennaPerformance]

Originally Posted by KingOfJericho

I just called your parts department and was given a price of $403.20 and they do not have them in stock. The website does say $243 but the guy said that must be incorrect.

You need to call McKenna Performance for our online pricing. They were probably trying to charge you full retail!

PM me if you need assistance sir

[Crulexis]

How would these sound with cattless DP's? I'm guessing that's a bad idea considering you have no more cats... Any thoughts?

Or how about the N55 Midpipes, Catless DP's and PE Exhaust

[conrad325i]

Originally Posted by Dackelone

Ok, here you go... I took some pics today.

OD is about 78mm's and ID is about 65mm's. 78mm's is just over 3"!



Attachment 815058

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Seeing a measuring tape in cm is odd for me. Haha.