Catless DP and Options to reduce smell

project jayden · 05-30-2016, 08:33 AM

magnaflow sells universal high flow cats in various sizes. just weld one in. should get rid of most of the smell and have similar gains

Orpo · 05-30-2016, 09:33 AM

Quote:

Originally Posted by project jayden

magnaflow sells universal high flow cats in various sizes. just weld one in. should get rid of most of the smell and have similar gains

I've been looking into to that as an option. But there are so many type and manufacturers of cats with prices all over the place. Its difficult to figure out which one I need to get.

Thanks

project jayden · 05-30-2016, 09:44 AM

Quote:

Originally Posted by Orpo

Quote:

Originally Posted by project jayden

magnaflow sells universal high flow cats in various sizes. just weld one in. should get rid of most of the smell and have similar gains

I've been looking into to that as an option. But there are so many type and manufacturers of cats with prices all over the place. Its difficult to figure out which one I need to get.

Thanks

measure how much length of space you have under there and then just choose the correct diameter.

ShocknAwe · 05-30-2016, 10:14 AM

Quote:

Originally Posted by project jayden

magnaflow sells universal high flow cats in various sizes. just weld one in. should get rid of most of the smell and have similar gains

This is a great option.

What about this? Could replace the Y-pipe resonator with a 2-inlet cat, and put 2 12 inch vibrant bottle resonators where the secondary cats go on the N54 pipes.

Hmm. I wonder what the cell pack is for these magnaflow universals.

litebulb · 06-01-2016, 04:43 PM

I'm wondering, if I replaced the resonator on the N55 mids with a cat if it's too far down the line to warm up to proper operating temperature, what do you think?

Quote:

Originally Posted by ShocknAwe

This is a great option.

What about this? Could replace the Y-pipe resonator with a 2-inlet cat, and put 2 12 inch vibrant bottle resonators where the secondary cats go on the N54 pipes.

Hmm. I wonder what the cell pack is for these magnaflow universals.

HyeWarrior · 06-01-2016, 05:40 PM

Figures this thread would come up right before I was planning on getting a catless DP.

Oh jeez

ShocknAwe · 06-02-2016, 10:17 AM

Quote:

Originally Posted by litebulb

I'm wondering, if I replaced the resonator on the N55 mids with a cat if it's too far down the line to warm up to proper operating temperature, what do you think?

No idea. That was one of my initial questions as well. I will have my car up in the air this weekend. I'll try to remember to take some measurements to see if things will even fit.

Orpo · 06-02-2016, 10:28 AM

What about something like this?
We'd have to get 2 of them i suppose.

http://www.ebay.ca/itm/3-Magnaflow-U...iwrMCg&vxp=mtr

ShocknAwe · 06-02-2016, 10:36 AM

Quote:

Originally Posted by Orpo

What about something like this?
We'd have to get 2 of them i suppose.

http://www.ebay.ca/itm/3-Magnaflow-U...iwrMCg&vxp=mtr

Why would you need 2 of them? If you're replacing your resonator with a cat, you'd need a 2-inlet 1-outlet cat.

Orpo · 06-02-2016, 10:40 AM

Ok, I hadnt realized this could be done.
I'll have to do some searching for that type of configuration.

Orpo · 06-08-2016, 08:31 PM

So I found an N54 midpipe for sale in California on eBay.
I paid $140 USD + $20 USD shipping.

This way it's a direct bolt on and I have my N55 mids unmolested in case of resale

HyeWarrior · 06-09-2016, 12:40 AM

Irvine right? I saw that listing lol

Orpo · 06-09-2016, 08:18 AM

Quote:

Originally Posted by HyeWarrior

Irvine right? I saw that listing lol

Yep!
Its a long way from Cali to NY and then to Montreal, Canada....

qualitycontrol · 06-11-2016, 04:33 PM

I am looking at buying some high flow cats for this reason. I am waiting to hear from the seller but I was going to go catless and have heard this being an issue for some. I guess I could just go catless and leave my n54 mids in place. Decisions, decisions.

Who has what and whats the best option for sound and power. Catless with N54 mids, or high catted dp?

all4bspinnin · 06-11-2016, 09:05 PM

OP, I actually went through your exact same problem. I went catless downpipes not realizing how bad the N54 engine stunk! Its worse than my c6z with cam and catless headers was! It was so bad, my gf didnt want to ride in the car. I would stink like raw fuel, etc. It was bad.

What I ended up doing was going to N54 mids. I dont feel like I lost any power, the car sounded better, and best of all... no fuel smell! I highly recommend either going back to N54 mids or having some race cats welded in. You'll live happily ever after.

litebulb · 06-12-2016, 12:40 AM

I really wish BMW sold the y-pipe separately. I want a little more grunt, but I totally couldn't stand the smoking, fuel smell and the diesel truck sound with the N55 pipes and my catless DPs.

Quote:

Originally Posted by all4bspinnin

OP, I actually went through your exact same problem. I went catless downpipes not realizing how bad the N54 engine stunk! Its worse than my c6z with cam and catless headers was! It was so bad, my gf didnt want to ride in the car. I would stink like raw fuel, etc. It was bad.

What I ended up doing was going to N54 mids. I dont feel like I lost any power, the car sounded better, and best of all... no fuel smell! I highly recommend either going back to N54 mids or having some race cats welded in. You'll live happily ever after.

Orpo · 06-12-2016, 06:55 AM

Quote:

Originally Posted by all4bspinnin

OP, I actually went through your exact same problem. I went catless downpipes not realizing how bad the N54 engine stunk! Its worse than my c6z with cam and catless headers was! It was so bad, my gf didnt want to ride in the car. I would stink like raw fuel, etc. It was bad.

What I ended up doing was going to N54 mids. I dont feel like I lost any power, the car sounded better, and best of all... no fuel smell! I highly recommend either going back to N54 mids or having some race cats welded in. You'll live happily ever after.

Awesome thanks

all4bspinnin · 06-12-2016, 02:59 PM

No problem. I hope you get it catted. Im going to try to play around with the tune as well to see how much of a difference playing with VANOS overlap makes. I'll post up if I get positive results

HyeWarrior · 06-12-2016, 03:45 PM

Is there any specific reason why catted DP's are so ludicrously expensive? It's cheaper to just buy catless DP's and catted mids

all4bspinnin · 06-12-2016, 07:55 PM

Quote:

Originally Posted by HyeWarrior

Is there any specific reason why catted DP's are so ludicrously expensive? It's cheaper to just buy catless DP's and catted mids

Cats are expensive in general. They have platinum in them and im sure the manufacturing process is a large portion as well.

Many shops will even pay $50 to $100 for the cat off your downpipe because they can be refined in to platinum.

Its always going to be cheaper to go catless but the trade off is the horrible fuel/exhaust stench.

Orpo · 06-20-2016, 07:22 PM

Update
I purchased an N54 midpipe and installed it this weekend.
It bolted up perfectly and when I started the car, the smell was gone!

But unfortunately so was the sound 😩 I would estimate that 50% - 60% of the previous gloriousness is no longer there.

What do you guys recommend I can do?
Cut the Center resonator and replace with a Y pipe?
Any other cost effective options?
I do eventually want to get a quad exhaust. Should I just wait for that?
Thanks

ShocknAwe · 06-20-2016, 10:12 PM

Quote:

Originally Posted by Orpo

Update
I purchased an N54 midpipe and installed it this weekend.
It bolted up perfectly and when I started the car, the smell was gone!

But unfortunately so was the sound 😩 I would estimate that 50% - 60% of the previous gloriousness is no longer there.

What do you guys recommend I can do?
Cut the Center resonator and replace with a Y pipe?
Any other cost effective options?
I do eventually want to get a quad exhaust. Should I just wait for that?
Thanks

Y pipe is the first step I'd say.

05-30-2016, 08:33 AM	#23
project jayden First Lieutenant 76 Rep 376 Posts Drives: 2009 135i Join Date: Sep 2014 Location: murrieta iTrader: (1) Garage List 2009 135i [10.00]	magnaflow sells universal high flow cats in various sizes. just weld one in. should get rid of most of the smell and have similar gains
	Appreciate 1 Quote

06-01-2016, 05:40 PM	#28
HyeWarrior Major 747 Rep 1,119 Posts Drives: 2012 135i DCT Join Date: Aug 2010 Location: San Dimas, CA iTrader: (1)	Figures this thread would come up right before I was planning on getting a catless DP. Oh jeez
	Appreciate 0 Quote

06-02-2016, 10:28 AM	#30
Orpo Private First Class 26 Rep 149 Posts Drives: 2020 M2 Competition 6MT HS Join Date: Sep 2015 Location: Canada eh iTrader: (0)	What about something like this? We'd have to get 2 of them i suppose. http://www.ebay.ca/itm/3-Magnaflow-U...iwrMCg&vxp=mtr
	Appreciate 0 Quote

06-02-2016, 10:40 AM	#32
Orpo Private First Class 26 Rep 149 Posts Drives: 2020 M2 Competition 6MT HS Join Date: Sep 2015 Location: Canada eh iTrader: (0)	Ok, I hadnt realized this could be done. I'll have to do some searching for that type of configuration.
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06-08-2016, 08:31 PM	#33
Orpo Private First Class 26 Rep 149 Posts Drives: 2020 M2 Competition 6MT HS Join Date: Sep 2015 Location: Canada eh iTrader: (0)	So I found an N54 midpipe for sale in California on eBay. I paid $140 USD + $20 USD shipping. This way it's a direct bolt on and I have my N55 mids unmolested in case of resale
	Appreciate 0 Quote

06-09-2016, 12:40 AM	#34
HyeWarrior Major 747 Rep 1,119 Posts Drives: 2012 135i DCT Join Date: Aug 2010 Location: San Dimas, CA iTrader: (1)	Irvine right? I saw that listing lol
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06-11-2016, 04:33 PM	#36
qualitycontrol Private First Class 8 Rep 134 Posts Drives: 2008 BMW 135i - Alpine white Join Date: Oct 2015 Location: Hamilton, Ontario, Canada iTrader: (0)	I am looking at buying some high flow cats for this reason. I am waiting to hear from the seller but I was going to go catless and have heard this being an issue for some. I guess I could just go catless and leave my n54 mids in place. Decisions, decisions. Who has what and whats the best option for sound and power. Catless with N54 mids, or high catted dp? __________________ 2008 BMW 135i - Alpine White - Coral Red Interior - JB4 G5 w/ anti lag, 2 step, dp fix - ER CP with HKS BOV - BMS DCI - CPE Catted downpipes - Berk resonated mids with stock axle back - Waiting to be installed: ER Comp intercooler - H&R super sports
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06-11-2016, 09:05 PM	#37
all4bspinnin Second Lieutenant 38 Rep 206 Posts Drives: 09 135i LeMans Blue/Terracota Join Date: May 2015 Location: Jax, FL iTrader: (0)	OP, I actually went through your exact same problem. I went catless downpipes not realizing how bad the N54 engine stunk! Its worse than my c6z with cam and catless headers was! It was so bad, my gf didnt want to ride in the car. I would stink like raw fuel, etc. It was bad. What I ended up doing was going to N54 mids. I dont feel like I lost any power, the car sounded better, and best of all... no fuel smell! I highly recommend either going back to N54 mids or having some race cats welded in. You'll live happily ever after.
	Appreciate 1 Quote

06-12-2016, 02:59 PM	#40
all4bspinnin Second Lieutenant 38 Rep 206 Posts Drives: 09 135i LeMans Blue/Terracota Join Date: May 2015 Location: Jax, FL iTrader: (0)	No problem. I hope you get it catted. Im going to try to play around with the tune as well to see how much of a difference playing with VANOS overlap makes. I'll post up if I get positive results
	Appreciate 0 Quote

06-12-2016, 03:45 PM	#41
HyeWarrior Major 747 Rep 1,119 Posts Drives: 2012 135i DCT Join Date: Aug 2010 Location: San Dimas, CA iTrader: (1)	Is there any specific reason why catted DP's are so ludicrously expensive? It's cheaper to just buy catless DP's and catted mids
	Appreciate 0 Quote

06-20-2016, 07:22 PM	#43
Orpo Private First Class 26 Rep 149 Posts Drives: 2020 M2 Competition 6MT HS Join Date: Sep 2015 Location: Canada eh iTrader: (0)	Update I purchased an N54 midpipe and installed it this weekend. It bolted up perfectly and when I started the car, the smell was gone! But unfortunately so was the sound 😩 I would estimate that 50% - 60% of the previous gloriousness is no longer there. What do you guys recommend I can do? Cut the Center resonator and replace with a Y pipe? Any other cost effective options? I do eventually want to get a quad exhaust. Should I just wait for that? Thanks
	Appreciate 0 Quote