One is a ceramic substrate by magnaflow ... I am assuming I should use the smaller one

http://www.car-sound.com/universal/941.htm

http://www.car-sound.com/universal/530.htm (53006 p/n)


the other is a metallic substrate ... it is claimed that SS, Larini, and the PowerCat; not to mention both the US and Euro M3's have Metallic Subtrate cats.

Is there a difference between a metallic substrate catalytic converter and a ceramic substrate one? What's the difference?

Here is the metallic substrate one.

http://www.rpmoutlet.com/powercat.htm

Magnaflow is OBD-II compliant ... the powercats are not.

What would you recommend going with?

Off the top of my head, ceramic substrates tend to be more fragile then metallic. extensive heat cycles, impact damage and such take a toll on ceramic more then they do on metallic. Once the ceramic cracks it tends to break apart. Plus depending on the manufacturing process, ceramics tend to have thicker cell walls then metallic. The advantage of ceramic though is it tends to be cheaper.

I believe the OEM have ceramic cats... let me find this article...

I believe the OEM have ceramic cats... let me find this article...

here's an excerpt from a Larini article...

A Larini Systems 'GT' Cat is constructed around a single monolith (also known as the metallic substrate). The monolith is made up of 'Fe-Cr-Al' stainless steel and is constructed in a 'honeycomb', through which the exhaust gases pass. This monolith, unlike the sensitive stock ceramic monolith, can withstand temperatures of up to 1400°C, and is also extremely resistant to oxidation and corrosion. This endows a 'GT' Cat with exceptional durability.

here's an excerpt from a Larini article...

A Larini Systems 'GT' Cat is constructed around a single monolith (also known as the metallic substrate). The monolith is made up of 'Fe-Cr-Al' stainless steel and is constructed in a 'honeycomb', through which the exhaust gases pass. This monolith, unlike the sensitive stock ceramic monolith, can withstand temperatures of up to 1400°C, and is also extremely resistant to oxidation and corrosion. This endows a 'GT' Cat with exceptional durability.

and here's more info...

http://www.autocats.com/html/motorsport_frame.htm

Thanks Ced!

I don't really care about durability ... I could buy 10 magnaflows for the price of the larini exhaust :eek:

I believe the OEM have ceramic cats... let me find this article...

No they have metallic by Arvin Meritor...

Arvin Meritor M3 PDF (http://www.arvinmeritor.com/products/car/pdfs/bmw_m3_ext.pdf)


dave

Thanks Ced!

I don't really care about durability ... I could buy 10 magnaflows for the price of the larini exhaust :eek:
Did you check out PowerCat??

PowerCat metallic Subtrate cats... (http://www.rpmoutlet.com/powercat.htm)

You can build your own cat pipe for under $450.00. They are a 300CPI not the 200 CPI like the Larini, but they definitely flow better than any Ceramic cat. Dave.

here's an excerpt from a Larini article...

A Larini Systems 'GT' Cat is constructed around a single monolith (also known as the metallic substrate). The monolith is made up of 'Fe-Cr-Al' stainless steel and is constructed in a 'honeycomb', through which the exhaust gases pass. This monolith, unlike the sensitive stock ceramic monolith, can withstand temperatures of up to 1400°C, and is also extremely resistant to oxidation and corrosion. This endows a 'GT' Cat with exceptional durability.

Thats an advertisement form Bimmerworld, I wouldn't call that an article CED. Not to mention they are flat wrong. The OEM piece is a metallic substrate. See my post from the manafacturer of the OEM M3 exhaust. Once again, the US metallic substrate is a 500cpi, the euro is 400 cpi, and the Larini and SS are 200 CPI. Although, SS of Italy informed a board member and said they only sell even in the NA market a 100CPI metallic cat. Who knows, I don't think it will make that much of a difference. Dave.

Did you have any problems mounting it Dave? I am wavering back and forth b/w power cat and magnaflow.

Magnaflow is a bit larger though ... almost 1.5" wider than the powercats.

Anyone have pics of their custom cat setup?

Did you have any problems mounting it Dave? I am wavering back and forth b/w power cat and magnaflow.

Magnaflow is a bit larger though ... almost 1.5" wider than the powercats.


I didn't go with the PowerCat...didn't know about it at the time. I would have done it if I did. I got the SS race cat pipe, I got a smoking deal on the whole package as it was ordered by someone and they backed out the last minute.

You said that the PowerCats weren't OBDII compliant, they are. Thats why they went with a 300CPI vs. a 200CPI as they stated some cars were having diffuculties with a 200 or less cell count. Dave.

No they have metallic by Arvin Meritor...

Arvin Meritor M3 PDF (http://www.arvinmeritor.com/products/car/pdfs/bmw_m3_ext.pdf)


dave

hmmm...interesting...did you notice the numbers on the front page is for the Euro M3... It does say metallic;however, they produce more cats for the US, so maybe ceramic, only because it's cheaper???? hehehe... You know us on the other side of pond don't always get the goodies ;)...Thanks!

Clint -

I should have pictures in a week or two -- I am going to decide on which one to get by noon today. I am leaning toward powercats right now b/c it is 300 cell.

I thought the U.S. cats were 400 cell ... they are 500 cells?

The powercats are $135.00/each = $270.00 -- my mechanic will do it for free so,no labor cost.

The magnaflows will cost me around $140.00 total ... for both. Hmmm ... they are 200 cell cats.

Dave -- where are you getting that the powercats are EPA compliant? The magnaflows are certified compliant -- makes a big difference for emission purposes. The powercats, I don't see that certification ... I just see it is obd-ii compliant -- but, that is NOT the same as saying it is EPA certified. Am I missing something here?

'EPA' compliant and passing de' smog are two different things.... These cars run 3 times cleaner than most on the road today. I'm all about protecting the environment so as long as the computer sniffer can't tell the difference I don't care. My .02 Thanks.

Clint -

I should have pictures in a week or two -- I am going to decide on which one to get by noon today. I am leaning toward powercats right now b/c it is 300 cell.

I thought the U.S. cats were 400 cell ... they are 500 cells?

The powercats are $135.00/each = $270.00 -- my mechanic will do it for free so,no labor cost.

The magnaflows will cost me around $140.00 total ... for both. Hmmm ... they are 200 cell cats.

Dave -- where are you getting that the powercats are EPA compliant? The magnaflows are certified compliant -- makes a big difference for emission purposes. The powercats, I don't see that certification ... I just see it is obd-ii compliant -- but, that is NOT the same as saying it is EPA certified. Am I missing something here?

Magnaflow is OBD-II compliant ... the powercats are not.

You said they weren't OBD II compliant..I am saying they are..as far as EPA compliant, just removing a properly functioning converter is in violation of EPA regs. So if you are going to do it, get the best converter that you can. Also, a ceramic converter IMHO won't survive the rigors of a 8K rpm motor. If you are going to run a ceramic cat I would keep the OEM stuff on the car. It is a step in the wrong direction with ceramic cats. Belive me you are talking to a Mustang Cobra guy who has been running high flow ceramic cats since 1993. The metallic cat is where its at, in fact most the Mustang and ZO6 guys are running metallic cats because of their flow advantage over high flow ceramcic cats.

US cats are 500CPI, its the Euro cat thats 400...Dave

hmmm...interesting...did you notice the numbers on the front page is for the Euro M3... It does say metallic;however, they produce more cats for the US, so maybe ceramic, only because it's cheaper???? hehehe... You know us on the other side of pond don't always get the goodies ;)...Thanks!

Ced Ced Ced, what are we going to do with you. The US cats are a metallic subtrate....They use ArvinMeritor on the US car as well as the Euro car..the US car has metallic cats..."you can lead a horse to water, but you can never make him drink".....Dave.

Ced Ced Ced, what are we going to do with you. The US cats are a metallic subtrate....They use ArvinMeritor on the US car as well as the Euro car..the US car has metallic cats..."you can lead a horse to water, but you can never make him drink".....Dave.

ok, that's what you said ;) I know they use Arvin also...

Thanks guys ... just placed the order for the powercats. Should be in here, hopefully, three days. It was not bad $277.50 shipped. Great PRICE! Jeg's, summitpointracing, etc ... all want $149.99/EACH for it. I ordered from that rpm site.

I'll let you know how it goes and take pictures if you guys want.

Dave -- I also ordered that part -- thanks for your help with that! :)

Thanks guys ... just placed the order for the powercats. Should be in here, hopefully, three days. It was not bad $277.50 shipped. Great PRICE! Jeg's, summitpointracing, etc ... all want $149.99/EACH for it. I ordered from that rpm site.

I'll let you know how it goes and take pictures if you guys want.

Dave -- I also ordered that part -- thanks for your help with that! :)


cool. keep us posted.