BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read
      10-09-2021, 10:12 AM   #1
carl0s
New Member
6
Rep
26
Posts

Drives: 2004 545i & 2001 330i
Join Date: Jun 2013
Location: Manchester, England, UK

iTrader: (0)

M6 GC factory x-pipe ?

Hi

I am going to fit catless DPs, and have a remap.
I want the car to sound less like a dyson, maybe a bit raspy, or just more muscly.

I don't want to spend too much. M5 / M6 exhaust system prices are an absolute joke.

I'm going to do the DPs soon, and the map (bm3).
After that I'll attack the exhaust with a cutter and welder. I will start with removing the resonators

I'm unsure on the x-pipe though. It looks, from photos online, that there is already an x-pipe in there on the factory exhaust. Is that correct? No point cutting that out to fit another then?

thanks,
Carl
Appreciate 0
      10-10-2021, 12:52 PM   #2
Whipple
Lieutenant
Whipple's Avatar
232
Rep
549
Posts

Drives: 2015 BMW M6 Gran Coupe
Join Date: Jun 2011
Location: New York

iTrader: (0)

Quote:
Originally Posted by carl0s View Post
Hi

I am going to fit catless DPs, and have a remap.
I want the car to sound less like a dyson, maybe a bit raspy, or just more muscly.

I don't want to spend too much. M5 / M6 exhaust system prices are an absolute joke.

I'm going to do the DPs soon, and the map (bm3).
After that I'll attack the exhaust with a cutter and welder. I will start with removing the resonators

I'm unsure on the x-pipe though. It looks, from photos online, that there is already an x-pipe in there on the factory exhaust. Is that correct? No point cutting that out to fit another then?

thanks,
Carl
Hey ,if your car is a comp pack then the resonator tubes are hollow already ,
The problem with the factory exhaust giving a deeper tone is the midsection where the two pipes join ,I guess you can call it a baby X section its very pinched and choked,When you change the downpipes it will get much louder but the tone will be the same ,I attached a pic the Meistershaft Velocity box and you can see how much more opened it is vs stock, its also 3-1/2" tubing vs 3in
Attached Images
   
__________________
2015 M6 Gran Coupe> DME stage 3 tune back end flash>JB4 with Methanol control>Fabworx Catless downpipes>Full Meistershaft GTC exhaust 102mm GB tips>Built motor with Forged Cp Carillo Rods and Pistons > SSP spec X clutch > Stage 1 Pure Turbos>PG front mount intakes>PG charge coolers>Vorsteiner front and rear Carbon diffuser>Auto Tecknic Carbon shift paddles>3D Design aluminum pedals
Appreciate 2
      10-10-2021, 02:08 PM   #3
MMMM6GC
Second Lieutenant
155
Rep
255
Posts

Drives: M6 GC
Join Date: Nov 2019
Location: UK/USA

iTrader: (3)

Quote:
Originally Posted by Whipple View Post
Hey ,if your car is a comp pack then the resonator tubes are hollow already ,
The problem with the factory exhaust giving a deeper tone is the midsection where the two pipes join ,I guess you can call it a baby X section its very pinched and choked,When you change the downpipes it will get much louder but the tone will be the same ,I attached a pic the Meistershaft Velocity box and you can see how much more opened it is vs stock, its also 3-1/2" tubing vs 3in
Really great pics - thanks for posting! Would I be right in thinking that Meistershaft Velocity box can only be used with the Meistershaft muffler due to the difference in piping size vs OEM?

edit: answered my own question - you can get a reducer to join the velocity box to the factory piping - I'm assuming this is a generic part or something an exhaust shop could knock up easily?

Last edited by MMMM6GC; 10-10-2021 at 02:15 PM..
Appreciate 0
      10-10-2021, 03:57 PM   #4
Whipple
Lieutenant
Whipple's Avatar
232
Rep
549
Posts

Drives: 2015 BMW M6 Gran Coupe
Join Date: Jun 2011
Location: New York

iTrader: (0)

Quote:
Originally Posted by MMMM6GC View Post
Really great pics - thanks for posting! Would I be right in thinking that Meistershaft Velocity box can only be used with the Meistershaft muffler due to the difference in piping size vs OEM?

edit: answered my own question - you can get a reducer to join the velocity box to the factory piping - I'm assuming this is a generic part or something an exhaust shop could knock up easily?
Im sure a good exhaust shop can fabricate pipes to connect from 3 to 3.5
I would use a really good fabrication shop rather than a generic muffler shop, you want to make sure there using good materials for the job

I went the other route, I kept my stock exhaust intact, 2-1/2 years ago was able to purchase a Full Meistershaft GTC for a great price ,if I want to sell the car one day I would install the stock exhaust back on and sell the Meistershaft for close to what I paid for it
__________________
2015 M6 Gran Coupe> DME stage 3 tune back end flash>JB4 with Methanol control>Fabworx Catless downpipes>Full Meistershaft GTC exhaust 102mm GB tips>Built motor with Forged Cp Carillo Rods and Pistons > SSP spec X clutch > Stage 1 Pure Turbos>PG front mount intakes>PG charge coolers>Vorsteiner front and rear Carbon diffuser>Auto Tecknic Carbon shift paddles>3D Design aluminum pedals
Appreciate 1
MMMM6GC155.00
      10-10-2021, 04:59 PM   #5
MMMM6GC
Second Lieutenant
155
Rep
255
Posts

Drives: M6 GC
Join Date: Nov 2019
Location: UK/USA

iTrader: (3)

Quote:
Originally Posted by Whipple View Post
Im sure a good exhaust shop can fabricate pipes to connect from 3 to 3.5
I would use a really good fabrication shop rather than a generic muffler shop, you want to make sure there using good materials for the job

I went the other route, I kept my stock exhaust intact, 2-1/2 years ago was able to purchase a Full Meistershaft GTC for a great price ,if I want to sell the car one day I would install the stock exhaust back on and sell the Meistershaft for close to what I paid for it
That would be ideal really! I've been weighing up exhaust options for ages and haven't settled on what I want - or seen a deal for a good used system come up. I have the Comp package and at this point I'm leaning towards getting a Soul performance system (as it's very cost effective). But working upstream from there, the next restriction is the x-pipe, then the downpipes.

My thinking was to work my way up - see how I feel about the sound from the Soul exhaust ($1k). If i want more, get the velocity box ($1.6k). If I want more still, get DPs. It'll end up being a frankenstein set up but the flip-side is I can piecemeal the upgrades and stop when I'm satisfied?

The alternatives are Akra ($5-8k), full Meistershaft ($5k), full Eisenmann ($6.5k), and with all those I'm gambling on the sound until I purchase + install, and I may STILL want DPs.

I might get an estimate on the cost of a custom system DP-back from a local fabricator, but I suspect that would come out a similar price to these existing well-engineering options.
Appreciate 0
      10-10-2021, 06:38 PM   #6
MMMM6GC
Second Lieutenant
155
Rep
255
Posts

Drives: M6 GC
Join Date: Nov 2019
Location: UK/USA

iTrader: (3)

Also apologies for the thread-jack but hopefully OP will find this info useful. Would there be much difference between a Comp exhaust (with flaps wired open) vs muffler delete like Soul performance?
Appreciate 0
      10-24-2021, 12:02 AM   #7
yusoslo
New Member
2
Rep
6
Posts

Drives: ford escape
Join Date: Nov 2017
Location: richmond va

iTrader: (0)

I hope to be of some help.
I just bought a comp F12 and will be getting down pipes I plan on doing a double x pipe in place of
The factory x pipe and resonator. The goal is a higher pitch and more audible rev range as I feel
These cars can sound monotone.

I will be making videos of my experiment.
Appreciate 1
MMMM6GC155.00
      10-24-2021, 01:19 AM   #8
MMMM6GC
Second Lieutenant
155
Rep
255
Posts

Drives: M6 GC
Join Date: Nov 2019
Location: UK/USA

iTrader: (3)

Let us know how it goes and the shop you use! I'm not too far from you, would be amazing to hear the results!
Appreciate 0
      10-24-2021, 04:20 AM   #9
carl0s
New Member
6
Rep
26
Posts

Drives: 2004 545i & 2001 330i
Join Date: Jun 2013
Location: Manchester, England, UK

iTrader: (0)

Hi everybody, thanks for the replies and especially the photos. I didn't realise there had been replies here.
I have done the downpipes and a bootmod3 stage 2 aggressive burble. It's peaked my interest in the car again for now. I might want to get rid of the aggressive burble and change the X pipe instead though. At the moment it gets loud only with heavy throttle. It might be nice if it got louder with 1/3rd throttle, given the amount of power that there is, and wet roads etc.
I would be very interested in seeing/hearing the difference with the x pipe change Yusoslo, please keep us posted!
cheers,
Carl

Last edited by carl0s; 10-24-2021 at 04:27 AM..
Appreciate 0
      10-25-2021, 08:01 PM   #10
carl0s
New Member
6
Rep
26
Posts

Drives: 2004 545i & 2001 330i
Join Date: Jun 2013
Location: Manchester, England, UK

iTrader: (0)

Finally got some good weather today and quiet roads.
The car sounds and goes great.

I am getting clutch slip in 5th gear at ~5,000rpm.

I might do the XHP trans flash to increase clamping from 18bar to 20bar.
Appreciate 1
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 05:22 AM.




6post.com
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST