[Boostin335]

Hi everyone,

Looking to replace my secondary cats with pipes.

My guy said to just get the pipes and he will weld them on. So I am looking for a place or someone that will sell the pipes to do this, 1 on each side... question for you guys:

1) Stainless Steel is what I want?

2) Is there a specific diameter I need and certain length?

Any insight is appreciated thanks!

[D335NUTZ]

2.5" diameter if it's your stock midpipes.

[Brey335i]

Keep in mind that you will have to bend one of them

[Boostin335]

Originally Posted by Brey335i

Keep in mind that you will have to bend one of them

Only 1 and does it matter which side?

So 2 stainless pipes 2.5" diameter (YES everything is stock except the CYBA 4" tips but that isn't anywhere near the secondary cat)


Anyone have an idea the length? 6" 12" etc?

Below are pics from someone else doing it on a SEDAN, does it look the same underneath/parts wise on an e92 xi coupe?

[Boostin335]

any other help or suggestions where to get the pipes that work?

[Never-Enough]

Any exhaust shop should have piping on hand.

www.summitracing.com

[Boostin335]

is this what I need?

http://www.summitracing.com/parts/SUM-640125/

Stainless Steel 2.5" tubing .. 16 gauge is what we need?

Thanks for any help.

Looking to replace the secondary cats. 4 feet of this should be enough right?

[NiVeDh]

It's 2.36"

[Boostin335]

Originally Posted by NiVeDh

It's 2.36"

The stock 1 is 2.36 your saying? Wilazn said its 2.5

They sell 2.25 and 2.5..so?

[Boostin335]

Anyone? want to order today.

Just need to know if that will work.

its 2.5" stainless steel exhaust tubing... and its 16gauge does this work for replacing secondary cats?

[Rotorocious]

Do you have downpipes as well?


YES 2.5 "
I didn't have to order anything, any decent exhaust shop will have piping.


FWIW, here is a pic of my install.
Had catless downpipes and then deleted the secondaries.
Sounded so horrible I went back with vibrant resonators and had them weld those in instead.

07 coupe

[Boostin335]

Originally Posted by Rotorocious

Do you have downpipes as well?


YES 2.5 "
I didn't have to order anything, any decent exhaust shop will have piping.


FWIW, here is a pic of my install.
Had catless downpipes and then deleted the secondaries.
Sounded so horrible I went back with vibrant resonators and had them weld those in instead.

07 coupe

Thank you for the reply.

The exhaust is STOCK except for tips that I had welded on.

The place doing the welding isn't an exhaust shop so to speak, so they guy (I know them) said get the piping and he will weld it on and replace those.

So here I am looking for piping that will work with all stock piping.

Alex @ Helix just measured stock piping and got 57 mm which is 2.25"

You said 2.5 but is that because of the downpipes you have?

I just need to know the piping, 4 ft will cover both sides. Does the gauge matter?

[Rotorocious]

Originally Posted by Boostin335

Thank you for the reply.

The exhaust is STOCK except for tips that I had welded on.

The place doing the welding isn't an exhaust shop so to speak, so they guy (I know them) said get the piping and he will weld it on and replace those.

So here I am looking for piping that will work with all stock piping.

Alex @ Helix just measured stock piping and got 57 mm which is 2.25"

You said 2.5 but is that because of the downpipes you have?

I just need to know the piping, 4 ft will cover both sides. Does the gauge matter?

3" downpipes
The resonators I ordered were 2.5. But maybe the shop i went to was able to adjust the sizing a bit

[Boostin335]

Originally Posted by Rotorocious

3" downpipes
The resonators I ordered were 2.5. But maybe the shop i went to was able to adjust the sizing a bit

Alex said he wasnt 100% sure cause they don't do custom exhausts. I spoke to AR Design (msged them) and he said:

"Tubing is 2 3/8 IIRC. You can swedge 2.5" down to 2 3/8."

So yeah you ordered 2.5 and then they made it fit to the 2 3/8 size it is -- and if you look above nivedh said its 2.36 - I am not a math guy so I dunno is 2.36 = 2 3/8?

[NiVeDh]

Stock exhaust piping has an OD of 60 mm (2.36"). Most aftermarket exhausts are 2.5".

[Boostin335]

the consensus is ill be ordering the 2.5 SS tubing from Summit.

Is anyone else wanting to do this because I will have extra since it comes in 4 ft tubing.

And I can give you it for cheap.

[chingy24]

I might take some depending on your price.

[hipnotic]

just go to any exhaust shop they carry piping. I have no clue where you can go to just buy piping. But like what others have said you would need a 2.5" piping and two of them. I believe stainless steel is the best to go with.

[Boostin335]

Originally Posted by josh06lau

just go to any exhaust shop they carry piping. I have no clue where you can go to just buy piping. But like what others have said you would need a 2.5" piping and two of them. I believe stainless steel is the best to go with.

Just getting it from Summit Racing (link above).. they give it out in 4 ft measurements.. I will have enough for at least 1 other car, maybe 2.

For the guy that's interested. I am ordering it tonight, and will have the shop measure the length they need for both cats. I will post up how many cars worth I have and we can go from there. This should be sometime early-mid next week.

[bkrM3]

Very interested in the result of this...

Have you come across any info on whether this has any effect on NJ (or in my case PA) emissions testing?

[Boostin335]

Originally Posted by bkr335

Very interested in the result of this...

Have you come across any info on whether this has any effect on NJ (or in my case PA) emissions testing?

None. They don't do a visual - doesn't throw any check engine lights, and adds a little sound - nothing earth shattering, but noticeable.


On ANOTHER NOTE:

Buying the SS tubing now... I am getting 4 feet. I will have left over piping. Let me know if anyone wants enough to do this, I will send to you and it will be cheap