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Chris@Sprsprnt
Thu, Jan-27-2005, 10:18:49 PM
Group

Here are some images of various catalysts. This will show the benefit of going from ceramic to metallic and the various surface areas that metallic catalysts offer. If you have any questions please do not hesitate to ask.

This is a ceramic catalyst from a project car at BMP after only ~5,000 of hard use :eek2:
http://www.supersprintna.com/images/cats/CeramicBad400PSI.jpg

This is what that catalyst began life as before the abuse.
http://www.supersprintna.com/images/cats/CeramicGood400PSI.jpg

Here is a 400 CPI metallic catalyst that some OEMs use for high performance applications.
http://www.supersprintna.com/images/cats/Metallic400PSI.jpg

Here is a 200 CPI metallic catalyst that Supersprint uses for engines that need a certain amount of back pressure. See the reduction in surface area over the ceramic and even the 400 CPI metallic catalysts.
http://www.supersprintna.com/images/cats/Metallic200PSI.jpg

Here is a 100 CPI metallic catalyst that Supersprint uses for larger engines, such as BMW M, note the greatly reduced surface area for maximum flow.
http://www.supersprintna.com/images/cats/Metallic100PSI.jpg

Chris~aka the cats meow

moonlight
Thu, Jan-27-2005, 10:48:02 PM
Hey Chris,

Is your combination of headers/section 1 cats street legal? will they pass smog? I'm in cali.

Thanks!

BMWGuy206
Thu, Jan-27-2005, 10:54:02 PM
Thanks for the info. and pics Chris!!!

Rob's Archive
Thu, Jan-27-2005, 10:56:12 PM
cats meow,

thats a great pictoral here, but i have a few thoughts on that one...if you using a US spec cat in the 1st vs a euro in the 2nd, its not quite fair as they are farther down line so they get a little less heat, not much but a little.

Now also you didnt really show the comparison between the same amount of miles/hours between two setups.

Also while you posted, this is why you should use metalic vs ceramic...you never really said why other than the pictures.

I understand why, but some other members might like a little bit more "beef" behind the pictures.

good pics though

Chris@Sprsprnt
Thu, Jan-27-2005, 11:06:27 PM
moonlight

That's a great question! Technically replacing the OEM catalysts would not be smog legal. Maybe some CA members would like to share their experiences with smog in CA with this modification. Keep in mind that for a new car you do not have to get smog checked for years. This is a great modification for the s54 providing vast improvements in flow over the US setup! Chris

Chris@Sprsprnt
Thu, Jan-27-2005, 11:14:07 PM
BMWGuy206

I'm glad you like them. Rumor has it you are going with 100 cell metallic catalysts...

Chris@Sprsprnt
Thu, Jan-27-2005, 11:39:01 PM
Triflowm5+M3

Good points! To clarify my first to images let me further explain. The first image is an OEM ceramic catalyst from a Mini S with ~5,000 miles of hard use. The second is an OEM ceramic catalyst from a Mini S with zero miles. The first picture shows that the ceramic melts from hot spots and increases the surface area thus impeding the flow. The second picture shows the "thick" walls of the ceramic versus the thinner effective walls of the metallic catalysts. The metallic catalysts do not melt down like the ceramic catalysts, this provides a more consistent free flow over the life of the catalyst. The smaller the surface area equals the greater the flow, the greater the flow equals less back pressure, the less back pressure equals the greater hp freed up at the upper end of the RPM range. Chris

BMWGuy206
Thu, Jan-27-2005, 11:56:33 PM
BMWGuy206

I'm glad you like them. Rumor has it you are going with 100 cell metallic catalysts...

YES!!! I cant wait to get them installed. I need to get a baseline dyno though before installing it.

Rob's Archive
Fri, Jan-28-2005, 03:15:28 AM
chris...theres the info i was looking for. Thanks

Will Pwr
Fri, Jan-28-2005, 03:41:46 AM
moonlight

That's a great question! Technically replacing the OEM catalysts would not be smog legal. Maybe some CA members would like to share their experiences with smog in CA with this modification. Keep in mind that for a new car you do not have to get smog checked for years. This is a great modification for the s54 providing vast improvements in flow over the US setup! Chris

Chris, you are 100% right on the fine print legal aspect that it would technically not be legal. Being in the aftermarket automotive manufactuer industry as well, Im all too familiar with this issue. :banghead:

Though not 100% legal, many times one can still pass the sniffer with aftermarket catalysts...and some SMOG stations merely look for the fact that you do have catalysts on the car... :peace:

Divexxtreme
Fri, Jan-28-2005, 03:59:41 AM
I like 100-cell cats.:thumbsup:

Sirius
Fri, Jan-28-2005, 05:02:20 AM
What do the OEM E46 and E36 use? My dad's 740's cat's internals broke into peices and got pluged up in side the tailpipe, causing hesitation. We had to replace them.

BMWGuy206
Fri, Jan-28-2005, 05:06:39 AM
What do the OEM E46 and E36 use? My dad's 740's cat's internals broke into peices and got pluged up in side the tailpipe, causing hesitation. We had to replace them.

Those are ceramic cats. A common problem on the M62 engines. Even replaced cats will fail.

MattMan
Fri, Jan-28-2005, 05:31:54 AM
Chris:

Can you provide more information on the criteria you all use to determine what cell concentration you use for certain cars? You mention some smaller engine cars need more cells to maintain a higher backpressure. Can you elaborate? What makes the S54 fit the less bp = good? Engine size?

Beowoulf
Fri, Jan-28-2005, 08:01:16 AM
Hey Chris,

Is your combination of headers/section 1 cats street legal? will they pass smog? I'm in cali.

Thanks!
I cali it is a crap shoot to do this. If you manage to pass the visual inspection, meaning the guy doesn't know what the oem configuration should be, then you have a 50/50 chance of passing smog if you make sure the cats are nice and hot when the test is done. I would have already done this to my car if I was sure I could get away with it but I don't want to deal with the headaches if it fails. Chris did make a good point, you don't get your first smog for 4-5 years so it's up to you.

STALKER
Fri, Jan-28-2005, 09:24:04 AM
If you are worried about smog test, then go with the Euro headers and cats, they should pass and still give you a nice increase in performance.

Chris@Sprsprnt
Fri, Jan-28-2005, 04:37:22 PM
BMWGuy206

I'm sure you will be thrilled with the end result. I'm looking forward to dynos :beer:

Chris@Sprsprnt
Fri, Jan-28-2005, 04:39:13 PM
Triflowm5+M3

I'm glad I could help clear this up. Nice quages, the Blitz color goes well with your sceme. Chris

Chris@Sprsprnt
Fri, Jan-28-2005, 04:41:51 PM
Will Pwr

Thank you for your valued input! Bringing your car in for smog at full operating temperature helps with the sniffer test as the metallic catalysts scrub better when HOT. Chris

Rob's Archive
Fri, Jan-28-2005, 04:45:02 PM
chris,

thanks for the good words...

Chris@Sprsprnt
Fri, Jan-28-2005, 04:59:10 PM
Divexxtreme

These 100 cell metallic catalysts will be critical for your forced induction application. OEM system would be like mowing your 2 acre yard with a push mower...Supersprint is 23hp 6 speed John Deer rider with headlights! Chris

Rob's Archive
Fri, Jan-28-2005, 05:04:54 PM
and just remember...if you push enough boost, you can always opt for the HJS (supplier of the actual cats to SS) real race cats instead of sport ones....

I wouldnt know anything about that though

Nixlimited
Fri, Jan-28-2005, 06:24:58 PM
and just remember...if you push enough boost, you can always opt for the HJS (supplier of the actual cats to SS) real race cats instead of sport ones....

I wouldnt know anything about that though

Chris - Thanks for the info, but like other said, I would like to see a metal catalyst after some use.

Rob - I love your sig pic, I am so jealous of your M5.

Rob's Archive
Fri, Jan-28-2005, 11:54:19 PM
dont be...youll have a car one day that will be just as crazy.

Super Gyros
Sat, Jan-29-2005, 01:56:51 AM
dont be...youll have a car one day that will be just as crazy.


Maybe just as crazy but not that fast...

Chris@Sprsprnt
Mon, Jan-31-2005, 11:00:31 PM
Nixlimited

I do not have any images of the metallic catalysts after use at this time. The next time we have a project car apart I will take an image for you though. The Supersprint metallic catalysts do not melt down, change shape or even change color over time. They are very efficient and durable in comparison to the ceramic catalysts. Chris

Antwerp
Mon, Jan-31-2005, 11:07:38 PM
:thumbsup: Great info!