which cats to delete?

slow4.7 · 04-26-2011, 02:47 PM

i have 2008 sedan 335i

how many catalyc converters do these cars have ?

which ones do i delete to gain something in the performance aspect of it.....i was told they have 4 cats...do i delete the first ones?

Syndicategt · 04-26-2011, 02:50 PM

4 cats total ( 1 on each downpipe and 1 on each mid pipe) Most people go full catless, but if you are not going to get aftermarket downpipes, most people delete the mids.

slow4.7 · 04-26-2011, 02:53 PM

Quote:

Originally Posted by Syndicategt

4 cats total ( 1 on each downpipe and 1 on each mid pipe) Most people go full catless, but if you are not going to get aftermarket downpipes, most people delete the mids.

dumb question, but will going full catless be a big performance gain than just going midless cats ??

will it sound like crap if i delete the mid cats, and keep stock muffler, or even going full catless and leaving stock mufflers??

AltecBX · 04-26-2011, 02:54 PM

Get the downpipes done; That's right after the turbos
When you delete the mids, the car becomes to loud. (civic loud)

slow4.7 · 04-26-2011, 03:00 PM

Quote:

Originally Posted by AltecBX

Get the downpipes done; That's right after the turbos
When you delete the mids, the car becomes to loud. (civic loud)

that sounds more like it lol ill delete those right after turbos.....i hate the riceburner sound

Proper Motion LLC · 04-26-2011, 03:36 PM

the bigger performance gain is removing the cats in the downpipes

slow4.7 · 04-26-2011, 03:47 PM

thanks

D335NUTZ · 04-26-2011, 05:23 PM

Delete the midpipe cats and buy a catless downpipe and win!

momstmg78 · 04-26-2011, 05:57 PM

going catless makes a great daily driver into a not so great daily driver. you lose alot of down low power and tons of rasp and vibration inside vehicle. After a week of the AA exhuast I put factory dp back exhaust on and sold the AA exhaust.

mke135i · 04-26-2011, 06:02 PM

^ 1 out of thousands... I just went with catless DPs and don't think the car is too loud. I can hear the turbos a lot more, but the exhaust note changed only a bit. I have the rest of the exhaust stock and I'm very happy with it.

momstmg78 · 04-26-2011, 06:33 PM

mke135, i said with full catless. I didn't say going catless dp but keeping factory dp back exhaust.

D335NUTZ · 04-26-2011, 06:53 PM

I'm on catless dp and catless AE Exhaust and it's fine for a daily driver. As long as you aren't WOT it's not loud, but has a nice sporty growl to it.

99three · 04-26-2011, 10:21 PM

Does anyone know what the gains are by removing the main cats (not the pre-cats)

JB335 · 04-26-2011, 11:05 PM

Quote:

Originally Posted by Wilazn

I'm on catless dp and catless AE Exhaust and it's fine for a daily driver. As long as you aren't WOT it's not loud, but has a nice sporty growl to it.

Same setup. The only time it's too LOUD is when you cold start the car in the garage. lol

04-26-2011, 02:47 PM	#1
slow4.7 Private 12 Rep 75 Posts Drives: blue 335i Join Date: Mar 2011 Location: texas iTrader: (0)	which cats to delete? i have 2008 sedan 335i how many catalyc converters do these cars have ? which ones do i delete to gain something in the performance aspect of it.....i was told they have 4 cats...do i delete the first ones?
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04-26-2011, 02:50 PM	#2
Syndicategt Brigadier General 155 Rep 3,730 Posts Drives: 335i Join Date: Sep 2009 Location: Nor Cal iTrader: (11)	4 cats total ( 1 on each downpipe and 1 on each mid pipe) Most people go full catless, but if you are not going to get aftermarket downpipes, most people delete the mids. __________________ 2008 BMW 335i e90 - Sold - Rob Beck Turbos / PROcede V5 / Aquamist HFS-4 / AR Downpipes / AE Exhaust / ER Comp FMIC / ER CP / TiAL BOV / Custom Intake / RPI Scoops / Quaife LSD / Swift-Koni Coilovers / DSS HS / Morr VS8.2 Sig Black / Michelin PSS / P3 Boost Guage / M3 body / M3 steering wheel / Adam's Rotors / Hawk HPS / SS lines /
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04-26-2011, 02:54 PM	#4
AltecBX Colonel 324 Rep 2,663 Posts Drives: BMW 335xi Sedan; BMW M3 ZCP Join Date: Nov 2007 Location: NYC iTrader: (0) Garage List 2018 BMW M3 ZCP [0.00] 2007 BMW 335Xi [0.00]	Get the downpipes done; That's right after the turbos When you delete the mids, the car becomes to loud. (civic loud) __________________ 335xi Sedan 6AT \| Weather(70-85°F) \| N54 Tune Comparison Chart \|\| N54 Turbo Upgrade Comparison Chart -PROcede Rev. 2.5 ~ v5 (3/17 maps) / JB4 (8/21 maps) / COBB (Stg2+FMIC LT Aggressive maps) †Procede Map2(UT 45 - IGN 40) Aggression Target 2.0 \| 0-60 in 4.0sec \|\| †Cobb E30 LT (35% Ethanol/65% 93 Octane) \| 0-60 in 3.9sec AR Design Catless DP \| BMS DCI + OCC \| ETS 5 FMIC \| Alpina B3 Trans Flash \|235/265 19" Michelin PSS
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04-26-2011, 03:36 PM	#6
Proper Motion LLC Custom Powder Coater 147 Rep 2,784 Posts Drives: White 335i Sedan Join Date: Dec 2008 Location: Orange County CA iTrader: (2)	the bigger performance gain is removing the cats in the downpipes __________________ www.propermotion714.com
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04-26-2011, 03:47 PM	#7
slow4.7 Private 12 Rep 75 Posts Drives: blue 335i Join Date: Mar 2011 Location: texas iTrader: (0)	thanks
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04-26-2011, 05:23 PM	#8
D335NUTZ The Blue Beast 142 Rep 5,665 Posts Drives: 2008 E92 335xi in Montego Blue Join Date: Jan 2011 Location: Queens, New York iTrader: (8)	Delete the midpipe cats and buy a catless downpipe and win! __________________ Cobb AP Stage 2+ \| BMS DCI \| UR Catless DP \| UR Chargepipe \| Tial BV 50mm \| BSH OCC \| ETS FMIC \| Eisenmann Race Exhaust \| KWv1 Coilovers \| Volk TE37 TC Kline Ed.
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04-26-2011, 05:57 PM	#9
momstmg78 Banned 12 Rep 376 Posts Drives: 335i sedan Join Date: Oct 2010 Location: Turkish's house iTrader: (0)	going catless makes a great daily driver into a not so great daily driver. you lose alot of down low power and tons of rasp and vibration inside vehicle. After a week of the AA exhuast I put factory dp back exhaust on and sold the AA exhaust.
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04-26-2011, 06:02 PM	#10
mke135i Lieutenant 19 Rep 436 Posts Drives: 2008 BMW 135i Cabrio Join Date: Sep 2010 Location: Midwest iTrader: (3) Garage List 2008 135i [0.00]	^ 1 out of thousands... I just went with catless DPs and don't think the car is too loud. I can hear the turbos a lot more, but the exhaust note changed only a bit. I have the rest of the exhaust stock and I'm very happy with it.
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04-26-2011, 06:33 PM	#11
momstmg78 Banned 12 Rep 376 Posts Drives: 335i sedan Join Date: Oct 2010 Location: Turkish's house iTrader: (0)	mke135, i said with full catless. I didn't say going catless dp but keeping factory dp back exhaust.
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04-26-2011, 06:53 PM	#12
D335NUTZ The Blue Beast 142 Rep 5,665 Posts Drives: 2008 E92 335xi in Montego Blue Join Date: Jan 2011 Location: Queens, New York iTrader: (8)	I'm on catless dp and catless AE Exhaust and it's fine for a daily driver. As long as you aren't WOT it's not loud, but has a nice sporty growl to it. __________________ Cobb AP Stage 2+ \| BMS DCI \| UR Catless DP \| UR Chargepipe \| Tial BV 50mm \| BSH OCC \| ETS FMIC \| Eisenmann Race Exhaust \| KWv1 Coilovers \| Volk TE37 TC Kline Ed.
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04-26-2011, 10:21 PM	#13
99three Banned 25 Rep 838 Posts Drives: 993, e92, e36, F355, Z32, Jag Join Date: Sep 2010 Location: in the 416 iTrader: (3)	Does anyone know what the gains are by removing the main cats (not the pre-cats)
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