BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read
M2 Technical Topics > S55 Engine / Drivetrain / Exhaust / Bolt-ons / Tuning > Exhaust mods: realistic hp gains?

Post Reply
 
Thread Tools Search this Thread
      03-29-2019, 12:43 PM   #1
S55bruh
Private
74
Rep
67
Posts

Drives: Alpine White
Join Date: Sep 2018
Location: Deep South

iTrader: (0)

Exhaust mods: realistic hp gains?

I have a new DCT M2C, no mods. Factory rubber, MPSS.

I’d like a modest gain in hp/tq since I’ll be using stock tire widths. Something along the lines of 20-30hp would be fine with me.

My question is, can this be achieved with a complete exhaust overhaul from downpipes to exhaust tips?

I particularly like the new Lightweight HJS 200 catted downpipes for the M2C, along with Active Autowerke single midpipe and Eisenmann Racing exhaust variant. I’ve spoken with the manufacturers at Lightweight regarding their downpipes, and they assured me that it will not cause a CEL.

Does 20-30hp sound reasonable? I don’t particularly like the idea of flashing now that the new software has been released, plus I don’t want to risk being flagged by the dealer in case a warranty issue arises.

Thoughts?
Appreciate 0
      03-29-2019, 01:06 PM   #2
M4 GTS
Lieutenant
316
Rep
553
Posts

Drives: 02M3 19X3M40 on order 21 GT4
Join Date: Mar 2016
Location: Del Mar CA

iTrader: (0)

Yes probably around 20-30 but is going to be loud and raspy
Appreciate 0
      03-29-2019, 02:08 PM   #3
pz619
Brigadier General
3274
Rep
3,254
Posts

Drives: F87 M2C 6MT, Tesla 3
Join Date: Oct 2013
Location: San Diego

iTrader: (1)

Quote:
Originally Posted by S55bruh View Post
I have a new DCT M2C, no mods. Factory rubber, MPSS.

I’d like a modest gain in hp/tq since I’ll be using stock tire widths. Something along the lines of 20-30hp would be fine with me.

My question is, can this be achieved with a complete exhaust overhaul from downpipes to exhaust tips?

I particularly like the new Lightweight HJS 200 catted downpipes for the M2C, along with Active Autowerke single midpipe and Eisenmann Racing exhaust variant. I’ve spoken with the manufacturers at Lightweight regarding their downpipes, and they assured me that it will not cause a CEL.

Does 20-30hp sound reasonable? I don’t particularly like the idea of flashing now that the new software has been released, plus I don’t want to risk being flagged by the dealer in case a warranty issue arises.

Thoughts?
I think you can get close with a catted downpipe and mid-pipe. I did it on my M235i but I'm concerned with how raspy the S55 can get. I'm actually waiting to hear other cars first before I start monkeying around with the downpipes. If you do go with the lightweight 200 cat, let us know how it works/sounds!
Appreciate 0
      03-29-2019, 02:58 PM   #4
willy9123
New Member
willy9123's Avatar
76
Rep
29
Posts

Drives: BMW M2 Competition
Join Date: Jun 2018
Location: Vancouver Canada

iTrader: (0)

I still think a tune is a better way to go. Getting 20-30HP from exhaust is gonna make your car sound horrible.

Last edited by willy9123; 03-29-2019 at 03:00 PM.. Reason: mis-typed
Appreciate 0
      03-29-2019, 03:00 PM   #5
M4 GTS
Lieutenant
316
Rep
553
Posts

Drives: 02M3 19X3M40 on order 21 GT4
Join Date: Mar 2016
Location: Del Mar CA

iTrader: (0)

I had downpipes on my F80 and sound was nice. when I added Esenmann resonated mid pipe on stock exhaust sound was horrible. IMO S55 is very difficult engine to get excellent sound out of it. Its either down pipes only od mid and rear section without removing down pipes. Again this was my experience with F80.
Appreciate 0
      03-29-2019, 03:51 PM   #6
SEAT TIME RULES
Major
SEAT TIME RULES's Avatar
1095
Rep
1,261
Posts

Drives: 20 BMW M2C 17 Mazda MX-5 RF
Join Date: Oct 2006
Location: "Get Busy Living, or Get busy Dying"

iTrader: (0)

Garage List
2020 BMW M2C  [5.00]
There are several sound clips of the AA Midpipe with the OEM exhaust with downpipes. It sounds great and no rasp...
__________________
2005-2006 BMWCCA Boston Chapter president
2004 Mazda Rev It Up Finalist
2002-Present HPDE Instructor
My 2020M2C Build: https://f87.bimmerpost.com/forums/sh....php?t=1696726
Appreciate 0
      03-29-2019, 04:52 PM   #7
mike@x-ph.com
BimmerPost Supporting Vendor
mike@x-ph.com's Avatar
United_States
23788
Rep
190,143
Posts


Drives: 07-335/12-328/18-M4/21-M4CP
Join Date: Sep 2013
Location: Las Vegas

iTrader: (23)

Mufflers will not give you any performance increase, downpipes will add ~15-20 HP and the Active Autowerke midpipe another 15 HP... Catless downpipe + Active Autowerke midpipe and stock exhaust sound good
__________________
Check out our current sale by clicking on this link!
https://x-ph.com/sale/

Phone number 702-494-9435
Appreciate 0
      03-29-2019, 05:58 PM   #8
MR.
Colonel
MR.'s Avatar
No_Country
4397
Rep
2,856
Posts

Drives: BMW M2 CSL Turbomeister
Join Date: Sep 2013
Location: Travelling / Managing / Writing

iTrader: (0)

Garage List
Quote:
Originally Posted by mike@x-ph.com View Post
Mufflers will not give you any performance increase, downpipes will add ~15-20 HP and the Active Autowerke midpipe another 15 HP... Catless downpipe + Active Autowerke midpipe and stock exhaust sound good
Not 100% true! Depends on the muffler, but you can get a performance gain from a rear muffler. Just depends on which one you buy

MR
Appreciate 0
      03-29-2019, 07:53 PM   #9
mike@x-ph.com
BimmerPost Supporting Vendor
mike@x-ph.com's Avatar
United_States
23788
Rep
190,143
Posts


Drives: 07-335/12-328/18-M4/21-M4CP
Join Date: Sep 2013
Location: Las Vegas

iTrader: (23)

Quote:
Originally Posted by MR. View Post
Not 100% true! Depends on the muffler, but you can get a performance gain from a rear muffler. Just depends on which one you buy

MR
I have never seen a dyno showing real gains from a muffler (independent dynos) ... You might see 5-8 HP on a dyno, does not really count since its within the dyno's margin of error
__________________
Check out our current sale by clicking on this link!
https://x-ph.com/sale/

Phone number 702-494-9435
Appreciate 5
Poochie9099.00
MR RIZK756.50
David0ff1055.00
AndrewC198910903.50
      03-29-2019, 08:21 PM   #10
Kuervers
Second Lieutenant
80
Rep
231
Posts

Drives: 19 M2C HS,6sp 16 X5 35i
Join Date: May 2016
Location: lloydminster,ab

iTrader: (0)

downpipes I'll throw a cel and threaten warranty anyways. ps bm3 C's+ works great with stock tires
Appreciate 0
      03-30-2019, 08:13 AM   #11
Poochie
Luxury at the redline :)
Poochie's Avatar
United_States
9099
Rep
7,563
Posts

Drives: 2016 M2
Join Date: Aug 2012
Location: NYC

iTrader: (3)

Quote:
Originally Posted by mike@x-ph.com View Post
Quote:
Originally Posted by MR. View Post
Not 100% true! Depends on the muffler, but you can get a performance gain from a rear muffler. Just depends on which one you buy

MR
I have never seen a dyno showing real gains from a muffler (independent dynos) ... You might see 5-8 HP on a dyno, does not really count since its within the dyno's margin of error


I don't get some people; you actually sell exhausts, so you have an active interest in pushing them, yet you're being honest and people they still don't believe an exhaust, after the down pipes, adds no power, just noise.

Thanks for keeping it real!
Appreciate 1
ChrisK4449.00
      03-30-2019, 08:28 AM   #12
mike@x-ph.com
BimmerPost Supporting Vendor
mike@x-ph.com's Avatar
United_States
23788
Rep
190,143
Posts


Drives: 07-335/12-328/18-M4/21-M4CP
Join Date: Sep 2013
Location: Las Vegas

iTrader: (23)

Quote:
Originally Posted by Poochie View Post


I don't get some people; you actually sell exhausts, so you have an active interest in pushing them, yet you're being honesty and people they still don't believe an exhaust, after the down pipes, adds no power just noise.

Thank for keeping it real!
Thank you

From the dynos i have seen on the S55, a midpipe depending on the design can add power. After the midpipe, no real gains
__________________
Check out our current sale by clicking on this link!
https://x-ph.com/sale/

Phone number 702-494-9435
Appreciate 1
Poochie9099.00
      03-30-2019, 03:39 PM   #13
Big Fabri
Second Lieutenant
Big Fabri's Avatar
Italy
95
Rep
251
Posts

Drives: Lamborghini Huracan
Join Date: Mar 2019
Location: Italy

iTrader: (0)

it depends on many things. we saw a customer losing 70hp from an rs6 abt after changind the abt exhaust with a capirsto. We dyoned the car 3 times because and put another car because we initially thought the dyno went crazy. its a combinations of things.

a good exhaust shouln't be too restrictive to generate backpressure but narrow enoght to generate flow velocity to support the scavenging
Appreciate 0
      03-30-2019, 04:13 PM   #14
doughboy
Major General
doughboy's Avatar
1543
Rep
8,972
Posts

Drives: 2018 M2 Comp 6MT
Join Date: Jan 2009
Location: UK

iTrader: (2)

Quote:
Originally Posted by Big Fabri View Post
a good exhaust shouln't be too restrictive to generate backpressure but narrow enoght to generate flow velocity to support the scavenging
On a NA motor yes, but turbo charged engines just need the biggest exhaust possible post Turbo.

No exhaust at all after the turbo would be best, but obviously a bit noisy and not great for emissions!
Appreciate 0
      04-01-2019, 09:36 PM   #15
Ceramic Rabbit
Second Lieutenant
Ceramic Rabbit's Avatar
United_States
86
Rep
221
Posts

Drives: 2005 Honda Accord V6 Hybrid
Join Date: Aug 2016
Location: Washington, DC

iTrader: (0)

For 20-30 hp just do an easy tune, would be much much much cheaper than a full exhaust and considering the drivetrain is already detuned that much it's not like you will be pushing out more than it can handle.
Appreciate 0
      04-03-2019, 11:28 PM   #16
mike@x-ph.com
BimmerPost Supporting Vendor
mike@x-ph.com's Avatar
United_States
23788
Rep
190,143
Posts


Drives: 07-335/12-328/18-M4/21-M4CP
Join Date: Sep 2013
Location: Las Vegas

iTrader: (23)

Quote:
Originally Posted by Ceramic Rabbit View Post
For 20-30 hp just do an easy tune, would be much much much cheaper than a full exhaust and considering the drivetrain is already detuned that much it's not like you will be pushing out more than it can handle.
if power is the only goal from the mod, i fully agree with you
__________________
Check out our current sale by clicking on this link!
https://x-ph.com/sale/

Phone number 702-494-9435
Appreciate 0
      04-04-2019, 02:47 PM   #17
AutoTalent
Lieutenant General
AutoTalent's Avatar
2301
Rep
12,654
Posts

Drives: e92 M3 6mt | e60 M5 6mt
Join Date: Jul 2007
Location: Los Angeles

iTrader: (11)

Exhaust on the S55 doesn't really make a lot of power, you can easily attain more power with just a ECU flash.

Stage 1 alone for the M2C/S55 engine is about 60 WHP on 91 octane and 70 whp on 93.

Stage 2 requires downpipes, which adds more power with a nice bump in sound.

Here's a M2 Comp we installed downpipes on + flashed CaryTheLabelGuy Stage 2 E85

Appreciate 0
      04-05-2019, 08:41 PM   #18
Mr Pete
Major
Mr Pete's Avatar
No_Country
1596
Rep
1,000
Posts

Drives: 997 GT3 4.1, Golf R (daily)
Join Date: Aug 2014
Location: AZ

iTrader: (1)

I just installed the AA signature exhaust, and very pleased with the result. Can’t say for sure how much power increase there is, though that was not my intent when purchasing the exhaust (looking for different sound). I definitely feel a difference in throttle response. The car climbs rpms much faster than before, it’s like a totally different car now lol

Best of luck.
Appreciate 0
      04-05-2019, 09:09 PM   #19
mike@x-ph.com
BimmerPost Supporting Vendor
mike@x-ph.com's Avatar
United_States
23788
Rep
190,143
Posts


Drives: 07-335/12-328/18-M4/21-M4CP
Join Date: Sep 2013
Location: Las Vegas

iTrader: (23)

Quote:
Originally Posted by Mr Pete View Post
I just installed the AA signature exhaust, and very pleased with the result. Can’t say for sure how much power increase there is, though that was not my intent when purchasing the exhaust (looking for different sound). I definitely feel a difference in throttle response. The car climbs rpms much faster than before, it’s like a totally different car now lol

Best of luck.
Congrats!!

Please post a sound clip
__________________
Check out our current sale by clicking on this link!
https://x-ph.com/sale/

Phone number 702-494-9435
Appreciate 0
      04-05-2019, 10:01 PM   #20
Mr Pete
Major
Mr Pete's Avatar
No_Country
1596
Rep
1,000
Posts

Drives: 997 GT3 4.1, Golf R (daily)
Join Date: Aug 2014
Location: AZ

iTrader: (1)

Quote:
Originally Posted by mike@x-ph.com View Post
Congrats!!

Please post a sound clip
I’ll try to post one. I’ll have to finally try to utilize the go pro.

And can’t thank you enough, Mike. A bit of confusion with my order initially. But I’m happy I went the AA route, purchased from Mike.
Appreciate 0
      04-06-2019, 02:25 PM   #21
mike@x-ph.com
BimmerPost Supporting Vendor
mike@x-ph.com's Avatar
United_States
23788
Rep
190,143
Posts


Drives: 07-335/12-328/18-M4/21-M4CP
Join Date: Sep 2013
Location: Las Vegas

iTrader: (23)

Quote:
Originally Posted by Mr Pete View Post
I’ll try to post one. I’ll have to finally try to utilize the go pro.

And can’t thank you enough, Mike. A bit of confusion with my order initially. But I’m happy I went the AA route, purchased from Mike.
My pleasure
__________________
Check out our current sale by clicking on this link!
https://x-ph.com/sale/

Phone number 702-494-9435
Appreciate 0
      04-07-2019, 08:17 AM   #22
kvnchu
Private
13
Rep
96
Posts

Drives: z4m
Join Date: Apr 2012
Location: Diamond Bar, CA

iTrader: (0)

Question regarding gains with dP.

Would there be additional gains to be had on a bm3 cs tune for m2c plus a catless downpipe?

With stock everything else how loud would it be? There's no sound clips with stock m2c muffler and catless dP.

Also I know I can seach this but can bm3 tune out check engine light?
Appreciate 0
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 04:07 PM.




m2
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, 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