E90Post
 


PYSPEED
 
BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Powertrain and Drivetrain Discussions > NA Engine (non-turbo) / Drivetrain / Exhaust Modifications > 2nd cat del. & res del. keeping stk muffler



Reply
 
Thread Tools Search this Thread
      06-17-2014, 11:08 AM   #1
Rival
Lieutenant
 
Drives: 95 z28
Join Date: Jul 2012
Location: shytown

Posts: 416
iTrader: (0)

2nd cat del. & res del. keeping stk muffler

Anyone done anything like that??

I want improved exhaust flow but dont want it much louder than stock.

I know keeping the stock muffler will still holdback exhaust flow but it will keep things quiet.


Is this a waste?? ive searched sound clips for hours. no one has really done this.
__________________
2008 328i 6spd
1995 Z28 6spd - 377rwhp rip
Rival is offline  
0
Reply With Quote
      06-17-2014, 12:27 PM   #2
JTDahl
Private
 
Drives: 2011 BMW 328i E90
Join Date: Nov 2012
Location: Orange County, California

Posts: 61
iTrader: (0)

Try the headers first and if it isnt loud enough then you can take off the res. At least with headers there are proven gains.
JTDahl is offline  
0
Reply With Quote
      06-17-2014, 01:36 PM   #3
BMW..
Lieutenant
 
Drives: E46 M3 /E90
Join Date: May 2013
Location: Boca Raton FL

Posts: 498
iTrader: (0)

I deleted my 2ndary cats and muffler. Sounds awesome and pulls harder after the 2ndaries were cut
__________________
Mystic Blue E90
Phoenix Yellow E46
BMW.. is offline  
0
Reply With Quote
      06-17-2014, 01:43 PM   #4
GTKrockeTT
Private First Class
 
Drives:
Join Date: Sep 2007

Posts: 135
iTrader: (1)

headers, slight audible increase.

headers with PE exhaust and mid pipe...awesome LOUD!!! unfortunately, my middle aged ears did not enjoy it like i would have in my younger years. put the original exhaust back in and did a resonator delete (custom mid pipe).

headers and resonator delete, perfect
GTKrockeTT is offline  
0
Reply With Quote
      06-17-2014, 02:21 PM   #5
JTDahl
Private
 
Drives: 2011 BMW 328i E90
Join Date: Nov 2012
Location: Orange County, California

Posts: 61
iTrader: (0)

Quote:
Originally Posted by BMW..
I deleted my 2ndary cats and muffler. Sounds awesome and pulls harder after the 2ndaries were cut
Did you keep your resonator?
JTDahl is offline  
0
Reply With Quote
      06-17-2014, 03:03 PM   #6
Rival
Lieutenant
 
Drives: 95 z28
Join Date: Jul 2012
Location: shytown

Posts: 416
iTrader: (0)

i have no plans for headers.

i would just buy PE and del. the 2nd cats but dont want to spend a grand on a catback. just looking for more sound n power, but im doing coilovers & wheels soon so there isnt much left in the budget.

im going to del the 2nd cats for stright pipes or res's and toss in a y pipe in place of the stk res.

If i go with aftermarket resonator's in place of the cats i may try or am thinking of running a bullet muffler.

so it would be- aftermarket resonators for 2nd cats, y pipe in place of stk res and a stock or bullet muffler depending on what you guys think.

or stright pipes in place of 2nd cats, y pipe in place of stock res and a bullet muffler or keep stk. not sure what to do......?
__________________
2008 328i 6spd
1995 Z28 6spd - 377rwhp rip

Last edited by Rival; 06-17-2014 at 03:08 PM.
Rival is offline  
0
Reply With Quote
      06-17-2014, 04:37 PM   #7
JTDahl
Private
 
Drives: 2011 BMW 328i E90
Join Date: Nov 2012
Location: Orange County, California

Posts: 61
iTrader: (0)

I have stock headers and both cats but I have a y-pipe in place of my res and then straightpiped out to 2 3" tips and I love it. It drones a little bit 2-3k rpm but sounds great above 3.
JTDahl is offline  
0
Reply With Quote
      06-17-2014, 06:22 PM   #8
BMW..
Lieutenant
 
Drives: E46 M3 /E90
Join Date: May 2013
Location: Boca Raton FL

Posts: 498
iTrader: (0)

Quote:
Originally Posted by JTDahl View Post
Did you keep your resonator?
Yes. I have straight pipes where the cats are and where the muffler is. Stock header and resonator.
Muffler delete gives you volume while cat delete adds deeper tone with more gargle and popcorn. It's awesome
__________________
Mystic Blue E90
Phoenix Yellow E46
BMW.. is offline  
0
Reply With Quote
      06-18-2014, 02:15 AM   #9
dtea604
Lieutenant
 
dtea604's Avatar
 
Drives: 06 E90 325i
Join Date: Jan 2012
Location: Vancouver

Posts: 443
iTrader: (0)

Quote:
Originally Posted by BMW.. View Post
Yes. I have straight pipes where the cats are and where the muffler is. Stock header and resonator.
Muffler delete gives you volume while cat delete adds deeper tone with more gargle and popcorn. It's awesome
Could you post a video clip of your set up?
dtea604 is offline   Canada
0
Reply With Quote
      06-18-2014, 08:08 AM   #10
thakid22
Enlisted Member
 
Drives: 2006 E90 330i Sport 6AT
Join Date: May 2013
Location: Little Rock

Posts: 42
iTrader: (0)

I prefer the sound of the 2nd Cats Delete & Resonator Delete with
the stock muffler left intact. I heard this this combo, in person and the sound
was phenomenal. Depending on the sound you like, you may favor this over the PExhaust. It definitely sounds more refined than the muffler deletes too.

The PE's can have a bit of loudness during cold startup/warmup. Rasp can be a slight issue at times as well. Muffler Deletes are often afflicted by drone and/or undue boominess at certain conditions.

With the 2nds/Resonator Deleted + keeping the stock muffler, I found that the 330i produced a clean burble/growl at low rpms and a refined whir/growl at higher rpms.
Burble and mild snaps and pops were evident during deceleration with engine braking.

I am going to duplicate this setup on my own 330i within maybe a month.
I will be sure to post back here with vidz so everyone can see what it sounds like.
thakid22 is offline   United_States
0
Reply With Quote
      06-18-2014, 01:19 PM   #11
Rival
Lieutenant
 
Drives: 95 z28
Join Date: Jul 2012
Location: shytown

Posts: 416
iTrader: (0)

Quote:
Originally Posted by thakid22 View Post
I prefer the sound of the 2nd Cats Delete & Resonator Delete with
the stock muffler left intact. I heard this this combo, in person and the sound
was phenomenal. Depending on the sound you like, you may favor this over the PExhaust. It definitely sounds more refined than the muffler deletes too.

The PE's can have a bit of loudness during cold startup/warmup. Rasp can be a slight issue at times as well. Muffler Deletes are often afflicted by drone and/or undue boominess at certain conditions.

With the 2nds/Resonator Deleted + keeping the stock muffler, I found that the 330i produced a clean burble/growl at low rpms and a refined whir/growl at higher rpms.
Burble and mild snaps and pops were evident during deceleration with engine braking.

I am going to duplicate this setup on my own 330i within maybe a month.
I will be sure to post back here with vidz so everyone can see what it sounds like.
well it looks like i wil be doing this soon.
__________________
2008 328i 6spd
1995 Z28 6spd - 377rwhp rip
Rival is offline  
0
Reply With Quote
      06-19-2014, 12:03 AM   #12
thakid22
Enlisted Member
 
Drives: 2006 E90 330i Sport 6AT
Join Date: May 2013
Location: Little Rock

Posts: 42
iTrader: (0)

Quote:
Originally Posted by Rival View Post
well it looks like i wil be doing this soon.
Really can't go wrong with this...
thakid22 is offline   United_States
0
Reply With Quote
      06-19-2014, 11:31 AM   #13
mt145
Private First Class
 
mt145's Avatar
 
Drives: 2007 E90 328xi
Join Date: May 2013
Location: Indiana

Posts: 191
iTrader: (0)

Garage List
2007 BMW 328xi  [0.00]
I'm very curious to hear your results. My only worry is smell.
mt145 is offline   United_States
0
Reply With Quote
      06-19-2014, 11:45 AM   #14
Ali-323i
Lieutenant
 
Ali-323i's Avatar
 
Drives: 2007 323i (Cdn) 4dr E90
Join Date: May 2013
Location: Toronto, Canada

Posts: 484
iTrader: (0)

Garage List
2007 BMW 323i  [0.00]
Quote:
Originally Posted by thakid22 View Post
I am going to duplicate this setup on my own 330i within maybe a month.
I will be sure to post back here with vidz so everyone can see what it sounds like.
Looking forward to this, as I was thinking of either doing just Secondary cat delete, or secondary cat & Res delete, while keeping stock muffler.

The other option is a magnaflow muffler (keeping stock res, possibly still doing a secondary cat delete).

Looking for a little bit of volume, not too much, and a deeper tone. Don't want any drone or raspiness.
__________________
Ali-323i is offline   Canada
0
Reply With Quote
      06-19-2014, 09:50 PM   #15
JTDahl
Private
 
Drives: 2011 BMW 328i E90
Join Date: Nov 2012
Location: Orange County, California

Posts: 61
iTrader: (0)

Quote:
Originally Posted by BMW..
Quote:
Originally Posted by JTDahl View Post
Did you keep your resonator?
Yes. I have straight pipes where the cats are and where the muffler is. Stock header and resonator.
Muffler delete gives you volume while cat delete adds deeper tone with more gargle and popcorn. It's awesome
Do you have any drone?
JTDahl is offline  
0
Reply With Quote
      06-19-2014, 10:56 PM   #16
BMW..
Lieutenant
 
Drives: E46 M3 /E90
Join Date: May 2013
Location: Boca Raton FL

Posts: 498
iTrader: (0)

Quote:
Originally Posted by JTDahl View Post
Do you have any drone?
If I have drone it doesn't bother me. The second cat delete adds power and more popping and volume but not drone. It is the same amount of drone (if any) as a normal muffler delete
__________________
Mystic Blue E90
Phoenix Yellow E46
BMW.. is offline  
0
Reply With Quote
      06-22-2014, 07:03 PM   #17
thakid22
Enlisted Member
 
Drives: 2006 E90 330i Sport 6AT
Join Date: May 2013
Location: Little Rock

Posts: 42
iTrader: (0)

Quote:
Originally Posted by BMW.. View Post
If I have drone it doesn't bother me. The second cat delete adds power and more popping and volume but not drone. It is the same amount of drone (if any) as a normal muffler delete
Hard to imagine why BMW didn' t do this and call it the PE... It sounds so good, clean, vocal, but nonintrusive that it should have been stock. I guess they needed to keep the 2nd cats for ULEV status?
thakid22 is offline   United_States
0
Reply With Quote
      06-23-2014, 11:35 AM   #18
Ali-323i
Lieutenant
 
Ali-323i's Avatar
 
Drives: 2007 323i (Cdn) 4dr E90
Join Date: May 2013
Location: Toronto, Canada

Posts: 484
iTrader: (0)

Garage List
2007 BMW 323i  [0.00]
I'm assuming that BMW installed 2nd Cats for a reason... so what's the downside of doing a 2nd cat delete?

Any impact on emissions? I know regulations change from state to state (and province to province in Canada)... I'm in Toronto, Canada.
__________________
Ali-323i is offline   Canada
0
Reply With Quote
      06-25-2014, 04:36 AM   #19
thakid22
Enlisted Member
 
Drives: 2006 E90 330i Sport 6AT
Join Date: May 2013
Location: Little Rock

Posts: 42
iTrader: (0)

Cats are strictly for emission purposes. Upon removal emissions go up, but I don't know exactly how much..
thakid22 is offline   United_States
0
Reply With Quote
      06-25-2014, 09:14 AM   #20
avocet
Lieutenant
 
Drives: 2007 328i
Join Date: Sep 2010
Location: Vancouver bc

Posts: 496
iTrader: (0)

Tailpipe emissions go up dramatically with a cat delete.

I will not, personally, do a cat delete because of this.
avocet is offline  
0
Reply With Quote
      06-26-2014, 11:19 AM   #21
Rival
Lieutenant
 
Drives: 95 z28
Join Date: Jul 2012
Location: shytown

Posts: 416
iTrader: (0)

Quote:
Originally Posted by avocet View Post
Tailpipe emissions go up dramatically with a cat delete.

I will not, personally, do a cat delete because of this.
they dont do tailpipe testing anymore....not in any big metropolitan area.


the 2nd cats are after the o2's. your fine unless you get a visual too.
__________________
2008 328i 6spd
1995 Z28 6spd - 377rwhp rip
Rival is offline  
0
Reply With Quote
      06-28-2014, 02:59 PM   #22
e93boy
VP
 
e93boy's Avatar
 
Drives: Black on Tan leather E93,
Join Date: May 2012
Location: So Cal

Posts: 62
iTrader: (2)

by removing the secondary cats are there any potential error codes or CEL that may come up on the dash board? I currently have my res delete and a remus quad, it has a nice mild sound and No Drone but im looking for something more. I have considered a few options: 1. after cat upgrade all piping to 3" 2. remove 2nd cats. or 3. both cat removal and upgraded 3" piping. Any experience or help would be appreciated.
e93boy is offline   United_States
0
Reply With Quote
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
Forum Jump


All times are GMT -5. The time now is 10:15 PM.




e90post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
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