CSL and Euro Cats - 200 cell or 400 cell?
 

Alright, I am spending way too much time researching this and the answer just seems to be a tossup. I thought the euro cats were the same CPI as the CSL cats. Does anyone know if the standard e46 m3 european cats are 200 CPI or 400 CPI?

From what I've gathered so far - either from people selling in the FS section to this side and even other forums is:

US cats: 400 cell (but Dave04M3 swears they are 500 cell)
Euro cats: 400 cell or 200 cell - split about 50/50 each way
CSL cats: 200 cell (mikymu as a reference, but have even seen other members and even vendors claiming 100 cell).

Please cite your source and don't guess because you "think" you know. I thought I knew, but now I don't; there is just too much conflicting information out there.

Please help!

CSL/Euro Cats are 200
http://m3forum.net/m3forum/showthrea...ighlight=cats*

L'rules is pretty knowledgeable with CSL/Euro parts since he sells them all the time.

Yes, I am more confident in that the CSL cats are 200 cell, but as for the standard euro cats, I'm seeing 400 cell all over the place. That's why I want to clear this up. Thank you for your input. I have spoken with him a few times as well.

From my understanding CSL and euro cats are the same.

IIRC... my Euro/CSL cats is 200 cel

200...

Euro Cats: 200 CPI
According to the ArvinMeritor pdf file: http://www.m3resource.com/downloads/...ust_System.pdf
See paragraph 4.2.1

I'm fairly certain that this publication is describing the Euro and US exhaust for the E46 M3.

Just to be clear. These cats are 200 cell and you need two of them. So that is a total of 400. And then stock carted section is approx 900 per side totaling 1800?
Can you guys confirm my numbers?

Zoomz... doesn't work like that.

Cell ratings are in "CPSI" - "Cells Per Square Inch". So it's not additive.

Here's a visual from cats from one of my old cars:

http://img46.imageshack.us/img46/8856/AcuraTSX304.jpg
http://img46.imageshack.us/img46/982/AcuraTSX303.jpg

I cut that piece of paper to be exactly 1" long along the top side and laid it on the cell matrix. Notice that it spans exactly 20 holes or 'cells'. 20 x 20 = 400, this is what a 400 CPSI catalyst looks like inside. (Technically this is what a 400 cpsi 'square' catalyst looks like, as there are also circular spun catalysts and other types. Square are common for OEM though.)

Thank you norm! I was looking for that and alot of links to the ArvinMeritor document have been disabled. So if this answers the question, I still can't understand why there is such controversy over these being 200 or 400 cell or if CSL cats are actually less restrictive.

Reach - Thank you so much for posting this as this is quite valuable to the mystery at hand. As you have suggested that some other manufacturers use spun substrates, the catalyst in the M3 is spun as well. Any other input is greatly appreciated.