welding 2-300 cell cat into midpipes for catless DP application?

sonic1 · 05-11-2015, 07:11 AM

Any thoughts on welding 2-300 cell cat in midpipes to help capture the smell from uncatted vrsf 3" downpipes?

vrsf 3" / AR gaskets and bolts / 300 cell MagnaFlow cat into midpipes?

http://www.amazon.com/gp/aw/d/B000RQ...WmL&ref=plSrch

Thanks!

Stucks · 05-11-2015, 11:25 AM

try http://mandrelbendingsolutions.com/m...low-converter/

Blaster400 · 05-11-2015, 11:31 AM

I welded in 100 cell race cats and they work well. Less smell and smoke than completely catless.

still in school · 05-11-2015, 11:37 AM

how did it affect sound?

05-11-2015, 12:16 PM

Quote:

Originally Posted by Blaster400

I welded in 100 cell race cats and they work well. Less smell and smoke than completely catless.

What size are they?

05-11-2015, 12:17 PM

Quote:

Originally Posted by Stucks

try http://mandrelbendingsolutions.com/m...low-converter/

Have you been to their shop before? I've always been intrigued by there "heavy loaded" cats:
http://mandrelbendingsolutions.com/m...ded-converter/

Will two 4" cats fit on the stock midpipe?

Stucks · 05-11-2015, 12:30 PM

Quote:

Originally Posted by FCobra94

Have you been to their shop before? I've always been intrigued by there "heavy loaded" cats:
http://mandrelbendingsolutions.com/m...ded-converter/

Will two 4" cats fit on the stock midpipe?

Never been to their shop before. they are located in my state, however, and i do have two 100 cell 4 inch diameter race cats from them.

05-11-2015, 12:41 PM

Quote:

Originally Posted by Stucks

Never been to their shop before. they are located in my state, however, and i do have two 100 cell 4 inch diameter race cats from them.

Yeah, I live in AA Co, but haven't gotten a chance to check the place out yet either.

sonic1 · 05-11-2015, 01:47 PM

I decided against upgrading to built-in downpipe cats - just ordered two 200 cell heavy loaded cats and will review once welded into midpipes.

Hoping these don't smell and work as I believe!

Quote:

Originally Posted by FCobra94

Have you been to their shop before? I've always been intrigued by there "heavy loaded" cats:
http://mandrelbendingsolutions.com/m...ded-converter/

Will two 4" cats fit on the stock midpipe?

Blaster400 · 05-11-2015, 02:20 PM

Quote:

Originally Posted by still in school

how did it affect sound?

They barely affected sound at all.

Quote:

Originally Posted by FCobra94

What size are they?

MBS 3" 100 cell race cats.

catracer · 05-11-2015, 06:37 PM

I have just had 2 200 cell heavy loading cats welded in place of the resonators in my HKS exhaust system. I also had 2 post cat o2 sensor bungs welded in place as well.. I plan to have my catless down pipes and intermediate pipes up to the cats Swaintech White Lighting coated. My hope is that the cats will warm up fast enough to not set a inefficiency fault.

sonic1 · 05-16-2015, 01:53 AM

Where is the best place to weld the cats into the midpipes? Do new o2 bungsneed to be welded in, and wires extended as well?

05-18-2015, 08:17 AM

Quote:

Originally Posted by catracer

I have just had 2 200 cell heavy loading cats welded in place of the resonators in my HKS exhaust system. I also had 2 post cat o2 sensor bungs welded in place as well.. I plan to have my catless down pipes and intermediate pipes up to the cats Swaintech White Lighting coated. My hope is that the cats will warm up fast enough to not set a inefficiency fault.

Awesome! Looking forward to hearing your results.

catracer · 05-19-2015, 06:03 PM

I welded my 200 cell cats in place of the resonators that came my HKS exhaust system. I had 2 post O2 bungs welded in place and yes the wiring harness for the post cat sensors will need to be extended. Try a Google search for 335i HKS exhaust and you will see where the resonators are located.

06-19-2015, 10:19 AM

Quote:

Originally Posted by catracer

I welded my 200 cell cats in place of the resonators that came my HKS exhaust system. I had 2 post O2 bungs welded in place and yes the wiring harness for the post cat sensors will need to be extended. Try a Google search for 335i HKS exhaust and you will see where the resonators are located.

Any update on your setup? You getting any codes with the new configuration? Wondering how, if anything, changes after extending the cat wires as well.

sonic1 · 07-15-2015, 03:15 PM

Still have yet to install these on my car - can't wait to finally get these in

Quote:

Originally Posted by FCobra94

Any update on your setup? You getting any codes with the new configuration? Wondering how, if anything, changes after extending the cat wires as well.

optigrab · 07-15-2015, 05:30 PM

Is there a way to install these without needing to extend the 02 sensor wires?

05-11-2015, 07:11 AM	#1
sonic1 Private First Class 99 Rep 133 Posts Drives: BMW Join Date: Dec 2011 Location: USA iTrader: (3)	welding 2-300 cell cat into midpipes for catless DP application? Any thoughts on welding 2-300 cell cat in midpipes to help capture the smell from uncatted vrsf 3" downpipes? vrsf 3" / AR gaskets and bolts / 300 cell MagnaFlow cat into midpipes? http://www.amazon.com/gp/aw/d/B000RQ...WmL&ref=plSrch Thanks!
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05-11-2015, 11:25 AM	#2
Stucks Lieutenant Colonel 180 Rep 1,911 Posts Drives: 2017 F30 340i Xdrive Join Date: Oct 2010 Location: Montgomery County, MD iTrader: (12)	try http://mandrelbendingsolutions.com/m...low-converter/ __________________ Current: 2017 F30 340i xdrive Previous: 2008 e92 335i coupe: RB turbos, mach 116 race fuel, methanol, alot of boost. Previous: 2003 Honda Accord V6 coupe: AEM V2, zex 75 wet shot (sold)
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05-11-2015, 11:31 AM	#3
Blaster400 Captain 129 Rep 866 Posts Drives: BMW X3 35i, Porsche Macan S Join Date: Jul 2012 Location: Scottsdale AZ iTrader: (3) Garage List 2018 Porsche Macan S [0.00] 2012 BMW X3 35i [0.00]	I welded in 100 cell race cats and they work well. Less smell and smoke than completely catless. Attached Images __________________ MOTIV 750 ST \| MOTIV PI \| 100% E85 \| Fuel-it Stage 4 LPFP \| MOTIV Boost Box + MHD Protune \| Quaife \| Öhlins \| Brembo \| Akrapovic
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05-11-2015, 11:37 AM	#4
still in school Private First Class 3 Rep 108 Posts Drives: e92 335i Join Date: Nov 2014 Location: Houston, Tx iTrader: (3)	how did it affect sound?
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05-11-2015, 06:37 PM	#11
catracer New Member 3 Rep 20 Posts Drives: 335i e92 Join Date: Jul 2009 Location: dc metro area iTrader: (0)	200 cell cats I have just had 2 200 cell heavy loading cats welded in place of the resonators in my HKS exhaust system. I also had 2 post cat o2 sensor bungs welded in place as well.. I plan to have my catless down pipes and intermediate pipes up to the cats Swaintech White Lighting coated. My hope is that the cats will warm up fast enough to not set a inefficiency fault.
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05-16-2015, 01:53 AM	#12
sonic1 Private First Class 99 Rep 133 Posts Drives: BMW Join Date: Dec 2011 Location: USA iTrader: (3)	Where is the best place to weld the cats into the midpipes? Do new o2 bungsneed to be welded in, and wires extended as well?
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05-19-2015, 06:03 PM	#14
catracer New Member 3 Rep 20 Posts Drives: 335i e92 Join Date: Jul 2009 Location: dc metro area iTrader: (0)	I welded my 200 cell cats in place of the resonators that came my HKS exhaust system. I had 2 post O2 bungs welded in place and yes the wiring harness for the post cat sensors will need to be extended. Try a Google search for 335i HKS exhaust and you will see where the resonators are located.
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07-15-2015, 05:30 PM	#17
optigrab More Boost? 60 Rep 283 Posts Drives: 08 135i MSport 6AT Join Date: Apr 2015 Location: Southern PA iTrader: (2)	Is there a way to install these without needing to extend the 02 sensor wires?
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