help: just removed my second catts with straight pipes and sounds terible!

x800pro6 · 10-25-2012, 07:45 AM

hi guies, i just removed my second catts and sounds so bad, like really rattle tinny vibration sound, comming out of the back of the car (extreamly loud), i have, rr cattless downpipes, the rattle sound starts from 1.8k rpm till about 2.1k rmp when the car is under slight load. it sounds terrible!!!(it sounds like the muffler baffles are vibrating). i have jacked the car up and had a look, however i dont see anything rubbing on the exaust. the sound is so bad literally sounds like a honda civic with hole in exaust. the only time it sounds better is when i use DS mode as the car keeps the revs above 2k normally. i have tried golf tee mod and without. sounds a bit worse with the golf tee mod. please any help would be greatly appreciated! thank you!

x800pro6 · 10-25-2012, 07:46 AM

i also got bigger exaust tips welded on at the same time i got the second catts removed. definatly not the sound i was trying to achive from some of the circulating youtube vids.

Bobbybmw22 · 10-25-2012, 07:49 AM

Quote:

Originally Posted by x800pro6

i also got bigger exaust tips welded on at the same time i got the second catts removed. definatly not the sound i was trying to achive from some of the circulating youtube vids.

Wow soo happy you psted this up because i was about to do this myselff

enrita · 10-25-2012, 08:23 AM

you should have searched/asked before doing that. Especially with AT fully catless without any resonators it sounds like crap....

cn555ic · 10-25-2012, 08:32 AM

http://www.e90post.com/forums/showthread.php?t=336138

triggz · 10-25-2012, 09:29 AM

You're brave doing that setup without Vibrant resonators. Resonators will clean up that sound tremendously and you'll be very happy with the end result.

5soko · 10-25-2012, 09:31 AM

I am fully catless and no resonator.. stock mufflers. No strange sounds.

triggz · 10-25-2012, 09:42 AM

Quote:

Originally Posted by 5soko

I am fully catless and no resonator.. stock mufflers. No strange sounds.

Do you have mufflers?

5soko · 10-25-2012, 10:55 AM

Quote:

Originally Posted by triggz

Do you have mufflers?

Stock mufflers.

cstavaru · 10-25-2012, 11:06 AM

You need to weld Vibrant 1792 resonators instead of the cats, otherwise the sound is unbearably raspy. However once you put the resonators in, everything will come back to normal.

x800pro6 · 10-25-2012, 03:41 PM

thanx guies! the sound it terible sounds like the exaust is touching something. i think im just going to put the catts back in as the car does small a bit. i did notice a peformance imrovement removing the rear catts!! definatly! maby i drill a couple of holes in this one b4 putting it back in hahahah. dam n54 is running at its limit, wish there was a fuel upgrade so i could mount some massive turbos. so i dont have to do stupid things like remove my catts in a desperate move just to make more power. haha

x800pro6 · 10-25-2012, 03:44 PM

NEXT STEP, electric cutouts that work with pnumatics, and upen after 8psi.

x800pro6 · 12-01-2012, 09:11 PM

i put the catts back in, car smells like roses again haha. and sounds good. thanx guies

10-25-2012, 07:45 AM	#1
x800pro6 ZEE DEE 16 Rep 62 Posts Drives: 335i Join Date: May 2012 Location: Melbourne Australia iTrader: (0)	help: just removed my second catts with straight pipes and sounds terible! hi guies, i just removed my second catts and sounds so bad, like really rattle tinny vibration sound, comming out of the back of the car (extreamly loud), i have, rr cattless downpipes, the rattle sound starts from 1.8k rpm till about 2.1k rmp when the car is under slight load. it sounds terrible!!!(it sounds like the muffler baffles are vibrating). i have jacked the car up and had a look, however i dont see anything rubbing on the exaust. the sound is so bad literally sounds like a honda civic with hole in exaust. the only time it sounds better is when i use DS mode as the car keeps the revs above 2k normally. i have tried golf tee mod and without. sounds a bit worse with the golf tee mod. please any help would be greatly appreciated! thank you!
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10-25-2012, 07:46 AM	#2
x800pro6 ZEE DEE 16 Rep 62 Posts Drives: 335i Join Date: May 2012 Location: Melbourne Australia iTrader: (0)	i also got bigger exaust tips welded on at the same time i got the second catts removed. definatly not the sound i was trying to achive from some of the circulating youtube vids.
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10-25-2012, 08:23 AM	#4
enrita Major General 163 Rep 7,377 Posts Drives: 335i - Big turbos Join Date: Sep 2008 Location: Italian in Sweden iTrader: (0)	you should have searched/asked before doing that. Especially with AT fully catless without any resonators it sounds like crap.... __________________ 07 335i AT - MOTIV 750 - MHD E85 BMS flash - BMS PI - JB4G5 - Okada Coils - NGK 5992 Plugs - Helix IC - Snow Stg. 3 - Stett CP - Custom midpipes with 100 HJS Cats - Bastuck Quad - PSS10 - QUAIFE LSD - BMS OCC - Forge DVs - AR OC - ALCON BBK - M3 Chassi - Dinan CP - Velocity M rear Toe arms - Advan RZ-DF - LUX H8 - Level 10 AT upgrade
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10-25-2012, 08:32 AM	#5
cn555ic 485 Rep 18,331 Posts Drives: 335i Join Date: Jun 2007 Location: US iTrader: (6)	http://www.e90post.com/forums/showthread.php?t=336138
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10-25-2012, 09:29 AM	#6
triggz Banned 61 Rep 1,224 Posts Drives: E92 335i Join Date: Jun 2010 Location: Toronto iTrader: (2)	You're brave doing that setup without Vibrant resonators. Resonators will clean up that sound tremendously and you'll be very happy with the end result.
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10-25-2012, 09:31 AM	#7
5soko Brigadier General 358 Rep 4,633 Posts Drives: M5 Join Date: Aug 2007 Location: Brooklyn, NY iTrader: (4)	I am fully catless and no resonator.. stock mufflers. No strange sounds. __________________ Current: E63S AMG 4matic RENNtech \|\| M5 Evolve..Eventuri \|\| F10 LCI 535i MHD
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10-25-2012, 11:06 AM	#10
cstavaru Brigadier General 334 Rep 3,262 Posts Drives: 2009 335i M Sport Sedan 6MT Join Date: Aug 2008 Location: Bucharest, Romania iTrader: (0)	You need to weld Vibrant 1792 resonators instead of the cats, otherwise the sound is unbearably raspy. However once you put the resonators in, everything will come back to normal. __________________ Mods(click): Cobb + RB Turbos \| Aquamist HFS-4 Meth \| Drexler LSD \| Bilstein B12 Pro-Kit \| Custom K&N Apollo Intake \| Wagner Intercooler \| Macht Schnell Downpipes \| BMW Performance Power Kit \| BMW Performance Exhaust \| BMW Performance Short Shifter \| M3 Subframe Bushings \|
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10-25-2012, 03:41 PM	#11
x800pro6 ZEE DEE 16 Rep 62 Posts Drives: 335i Join Date: May 2012 Location: Melbourne Australia iTrader: (0)	thanx guies! the sound it terible sounds like the exaust is touching something. i think im just going to put the catts back in as the car does small a bit. i did notice a peformance imrovement removing the rear catts!! definatly! maby i drill a couple of holes in this one b4 putting it back in hahahah. dam n54 is running at its limit, wish there was a fuel upgrade so i could mount some massive turbos. so i dont have to do stupid things like remove my catts in a desperate move just to make more power. haha
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10-25-2012, 03:44 PM	#12
x800pro6 ZEE DEE 16 Rep 62 Posts Drives: 335i Join Date: May 2012 Location: Melbourne Australia iTrader: (0)	NEXT STEP, electric cutouts that work with pnumatics, and upen after 8psi.
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12-01-2012, 09:11 PM	#13
x800pro6 ZEE DEE 16 Rep 62 Posts Drives: 335i Join Date: May 2012 Location: Melbourne Australia iTrader: (0)	i put the catts back in, car smells like roses again haha. and sounds good. thanx guies
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