Gut the factory cats or buy catless?

hov333 · 08-14-2008, 08:53 PM

The only reason why I rather gut the existing cats is because that way it will still look completely stock on a lift and I don't have to worry about the construction/welds. I figure if I ever want to go back to catted, I'll by a HFC from RR or UR.

Is there any sound difference between gutted cats and say RR or UR catless pipes? I ask because of the tapering of the OEM pipes vs. same diameter piping that the other brands offer.

Please share your experiences. Thanks!

e90AW335i · 08-14-2008, 08:57 PM

If you are ever going to go back into the dealership with cats than you need your stock pipes. If not, just gut them.

I voted to buy catless because it is cheap and effective.

hov333 · 08-14-2008, 09:10 PM

^thanks for the advice, the thing is that my car is an xi and its supposed to be a pain to switch the pipes and I rather go with an option that wont force me to be switching them often, cuz I know i'm going to have to go into the dealer sooner or later, and i dont want to worry about it much.

side note, is it expensive to have them gutted? I'm supposed to go into a shop tomoro so I'll post what they quote me.

vase330 · 08-14-2008, 09:23 PM

Don't gut it because its not worth it at all, plus what e90AW335i said.

SV Concepts III · 08-14-2008, 10:43 PM

I'd recommend purchasing the Riss Racing Catless pipes. That way you can easily turn the car back to stock if you need to and you don't have to worry about custom installations. Give me a call tomorrow Hovik or drop me an email and we can set you up with the Riss versions.

camaross305 · 08-15-2008, 12:04 AM

there is a member selling gutted stock downpipes in the forsale section. I dunno with the bends of the stock pipes i think aftermarket dp's will give you slightly more power not to mention tey are lighter. Is the extra 400-500$ worth about 6-10 more hp over stock gutted dp's? i dunno thats up to you.......either way catless dp's and a tune will unleash the beast

hov333 · 08-15-2008, 12:15 PM

thanks for all the comments! I wanted to retain the factory look which is why i was considering gutting. It is a pain to switch pipes on an xi, I want to avoid paying $300-400 to switch them everytime I go into the dealer...the less headache the better. I'm heading to a muffler shop in a few hours so I'll see what they quote me for both procedures as well.

keep the votes coming lol

e.n335 · 08-15-2008, 12:58 PM

I guess you miss something here. Of course, the DP's will look like stock but will not behave like stock. So the dealership will know the difference.

Turkishexpress · 08-15-2008, 01:10 PM

I was going to get a catless DP as well but according to my friend who is a service manager at FFX BMW, there is a clear coat seal on the stock DPs (where it connects to the turbo) which are damaged when you remove them. So even if you change it back to stock and there is engine issues and they happen to take a look at them, they can void your warranty

You don't have to pay any money to gut your cats btw. Just put some leaded gas in your car and drive around for at least two tanks and it should turn your cats into ashes and dump it all out the back. Do this on your own risk obviously.

hov333 · 08-15-2008, 01:13 PM

^lol thanks for that note

well it looks like I will probably buy myself a set of UR catless pipes since RR doesn't have one for the xi. I know i'm never going to go back to stock. If I were to change my mind I would just buy a high flow version. But if I go this route I will have an extra pair (oem) laying around.

View Poll Results: Gut OEM or buy already catless pipes?
gut the factory pipes	4	15.38%
pay more and buy already catless pipes	22	84.62%
Voters: 26. You may not vote on this poll

08-14-2008, 08:53 PM	#1
hov333 Major 69 Rep 1,003 Posts Drives: 2016 M5 Join Date: Sep 2007 Location: Boston, MA iTrader: (1)	Gut the factory cats or buy catless? The only reason why I rather gut the existing cats is because that way it will still look completely stock on a lift and I don't have to worry about the construction/welds. I figure if I ever want to go back to catted, I'll by a HFC from RR or UR. Is there any sound difference between gutted cats and say RR or UR catless pipes? I ask because of the tapering of the OEM pipes vs. same diameter piping that the other brands offer. Please share your experiences. Thanks!
	Appreciate 0 Tweet Quote

08-14-2008, 08:57 PM	#2
e90AW335i Major General 144 Rep 6,608 Posts Drives: e90 335i Join Date: Sep 2007 Location: ...... iTrader: (4)	If you are ever going to go back into the dealership with cats than you need your stock pipes. If not, just gut them. I voted to buy catless because it is cheap and effective. __________________ I install all tunes, intakes, o2 simms, and most cosmetic mods. PM me for a quote.
	Appreciate 0 Quote

08-14-2008, 09:10 PM	#3
hov333 Major 69 Rep 1,003 Posts Drives: 2016 M5 Join Date: Sep 2007 Location: Boston, MA iTrader: (1)	^thanks for the advice, the thing is that my car is an xi and its supposed to be a pain to switch the pipes and I rather go with an option that wont force me to be switching them often, cuz I know i'm going to have to go into the dealer sooner or later, and i dont want to worry about it much. side note, is it expensive to have them gutted? I'm supposed to go into a shop tomoro so I'll post what they quote me.
	Appreciate 0 Quote

08-14-2008, 09:23 PM	#4
vase330 Colonel 103 Rep 2,760 Posts Drives: 19 E63S; 15.5 RangeRover ATB Join Date: Jan 2007 Location: Arlington, Va iTrader: (1)	What e90AW335i said. Don't gut it because its not worth it at all, plus what e90AW335i said. __________________ E92 335 \| Space Gray \| Saddle Brown Dakota \| Dark Burl Trim \| ZPP \| ZSP \| AT \| Idrive \| 6FL \| FBO \| Dinan CAI \| Quaife LSD \| STG3 PROCede.
	Appreciate 0 Quote

08-14-2008, 10:43 PM	#5
SV Concepts III Lieutenant General 380 Rep 16,968 Posts Drives: BMW Duh Join Date: Apr 2005 Location: Santa Clara iTrader: (13)	I'd recommend purchasing the Riss Racing Catless pipes. That way you can easily turn the car back to stock if you need to and you don't have to worry about custom installations. Give me a call tomorrow Hovik or drop me an email and we can set you up with the Riss versions.
	Appreciate 0 Quote

08-15-2008, 12:04 AM	#6
camaross305 135 Rep 1,825 Posts Drives: 2008 M3 Join Date: Jul 2008 Location: gainesville fl iTrader: (20)	there is a member selling gutted stock downpipes in the forsale section. I dunno with the bends of the stock pipes i think aftermarket dp's will give you slightly more power not to mention tey are lighter. Is the extra 400-500$ worth about 6-10 more hp over stock gutted dp's? i dunno thats up to you.......either way catless dp's and a tune will unleash the beast
	Appreciate 0 Quote

08-15-2008, 12:15 PM	#7
hov333 Major 69 Rep 1,003 Posts Drives: 2016 M5 Join Date: Sep 2007 Location: Boston, MA iTrader: (1)	thanks for all the comments! I wanted to retain the factory look which is why i was considering gutting. It is a pain to switch pipes on an xi, I want to avoid paying $300-400 to switch them everytime I go into the dealer...the less headache the better. I'm heading to a muffler shop in a few hours so I'll see what they quote me for both procedures as well. keep the votes coming lol
	Appreciate 0 Quote

08-15-2008, 12:58 PM	#8
e.n335 Moderator 281 Rep 4,481 Posts Drives: e93 ///M3 DCT, 07/2009 Join Date: Feb 2007 Location: Switzerland, ZH iTrader: (0)	I guess you miss something here. Of course, the DP's will look like stock but will not behave like stock. So the dealership will know the difference.
	Appreciate 0 Quote

08-15-2008, 01:10 PM	#9
Turkishexpress Gixxer Man 14 Rep 599 Posts Drives: '08 335i E90 / '06 Range HSE Join Date: Aug 2008 Location: Tysons/Sterling, VA iTrader: (2)	I was going to get a catless DP as well but according to my friend who is a service manager at FFX BMW, there is a clear coat seal on the stock DPs (where it connects to the turbo) which are damaged when you remove them. So even if you change it back to stock and there is engine issues and they happen to take a look at them, they can void your warranty You don't have to pay any money to gut your cats btw. Just put some leaded gas in your car and drive around for at least two tanks and it should turn your cats into ashes and dump it all out the back. Do this on your own risk obviously. __________________ Stable: 2008 E90 335i JB3 etc..., 2006 Range Rover HSE, K7 GSX-R 600 Former Stable: 2008 MB C300, 2007 Chevy Avalanche, 2006 Evo IX (544awhp), 2005 Sti, 2003 Evo...
	Appreciate 0 Quote

08-15-2008, 01:13 PM	#10
hov333 Major 69 Rep 1,003 Posts Drives: 2016 M5 Join Date: Sep 2007 Location: Boston, MA iTrader: (1)	^lol thanks for that note well it looks like I will probably buy myself a set of UR catless pipes since RR doesn't have one for the xi. I know i'm never going to go back to stock. If I were to change my mind I would just buy a high flow version. But if I go this route I will have an extra pair (oem) laying around.
	Appreciate 0 Quote