Good vs. Bad Secondary Cats...
03-06-2009, 05:59 PM
#1
Former Vendor of MBWorld
Thread Starter
Good vs. Bad Secondary Cats...
Hello everyone,
One of our customers had high flow metal core cats installed and when we took the stock secondaries out were were quite surprised to see them almost completely deteriorated after only 50k. Most of the ceramic core was completely eaten through and gone (a good 75% of the cat core). This illustrates why metal core high flow cats are better as they are much more durable and last longer (just fyi). They are more expensive but worth the extra cost for this reason.
Just wanted to post this a public service announcement to all the CLK55 guys, and also just to show what the insides of secondary cats look like in case anyone was wondering.
enjoy..
~AMS~
One of our customers had high flow metal core cats installed and when we took the stock secondaries out were were quite surprised to see them almost completely deteriorated after only 50k. Most of the ceramic core was completely eaten through and gone (a good 75% of the cat core). This illustrates why metal core high flow cats are better as they are much more durable and last longer (just fyi). They are more expensive but worth the extra cost for this reason.
Just wanted to post this a public service announcement to all the CLK55 guys, and also just to show what the insides of secondary cats look like in case anyone was wondering.
enjoy..
~AMS~
Last edited by AMS Performance; 10-19-2011 at 09:08 PM.
03-06-2009, 06:40 PM
#2
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03 CLK 55 AMG, IMCO muffler/Magnaflow tips, KW V1 coilovers, 19" Petrol Metrix Wheels
It doesnt hurt that metal cats flow better too. In really bad case scenarious the ceramic material becomes dislodged and rattles around. it is truly an awful noise.
03-06-2009, 06:49 PM
#3
Former Vendor of MBWorld
Thread Starter
that is correct, or the cells themselves fuse shut and make the cats even more restrictive. The metal core cats are typically 200-300 cell, the ceramic cats are almost always 400 cell. Also the actual cores on the high flow aftermarket cats are only like 4-5" long where as the stock 400-cell cores are 8"+ so that in itself also helps with flow, not just the cell count.
03-07-2009, 08:49 AM
#4
MBWorld Fanatic!
Only problem that one will experience with the High flow cats is the fact that the stck rear O2's will unfortunately have the same/similar voltage readings as the front O2's and will give many a CEL. Especially when the primary cats are deleted.
Last edited by ProjectC55; 03-07-2009 at 09:07 AM.
03-07-2009, 10:42 AM
#5
MBWorld Fanatic!
Guys, I've been toying with the idea of playing with the 4 cats in my E350 exhaust. Not too long ago I found out that Brabus offered a tuning kit called the B7 package for the M272 350 motor. It consists of the 4 300 cell cats and their cat back exhaust (which I already have.) Brabus claims the car makes approx 200whp with this mod and based on dyno pulls w/ just the exhaust I'm currently making about 191whp. Now there are a couple things here I'm trying to figure out.
1st, Brabus says that this mod does not set and CEL's off, is this possible replacing all 4 w/ 300 cell cats?
2nd, Brabus says there is some type of special gel coating inside the cats to help with heat, what could that be/where do you think you can get this stuff? Jet Hot maybe?
3rd, Is it reasonable to expect that it will make me approx 9whp coupled with the cat back exhaust?
4th, Since they ask something like 10K for the four 300 cells and the exhaust, and I already have the exhaust, would it make sense to try to replicate this setup w/ universal 300 cell cats or do you think Brabus really knows something that warrants me spending all that extra money?
BRABUS B7
Base:
E350 (W211)
Power enhancement by back pressure lowering metal-catalytic converter (four monoliths with a full
OBD II suitability). The kit is completed by a matching stainless-steel end-muffler.
Technical data:
Displacement cm³ 3498
Compression ratio 10,7 : 1
Torque Nm 360 (350)
at min-1 2400 - 5000
Power output kW/PS 211 / 287 (200 / 272)
at min-1 6000
1st, Brabus says that this mod does not set and CEL's off, is this possible replacing all 4 w/ 300 cell cats?
2nd, Brabus says there is some type of special gel coating inside the cats to help with heat, what could that be/where do you think you can get this stuff? Jet Hot maybe?
3rd, Is it reasonable to expect that it will make me approx 9whp coupled with the cat back exhaust?
4th, Since they ask something like 10K for the four 300 cells and the exhaust, and I already have the exhaust, would it make sense to try to replicate this setup w/ universal 300 cell cats or do you think Brabus really knows something that warrants me spending all that extra money?
BRABUS B7
Base:
E350 (W211)
Power enhancement by back pressure lowering metal-catalytic converter (four monoliths with a full
OBD II suitability). The kit is completed by a matching stainless-steel end-muffler.
Technical data:
Displacement cm³ 3498
Compression ratio 10,7 : 1
Torque Nm 360 (350)
at min-1 2400 - 5000
Power output kW/PS 211 / 287 (200 / 272)
at min-1 6000
03-07-2009, 09:39 PM
#6
Former Vendor of MBWorld
Thread Starter
This was for secondaries so it doesn't have any effect on primaries or O2 readings. Furthermore, 300 cell cats can be used as primaries and you run a very low risk of CEL, where as 200 cell cats you are more likely to.
03-07-2009, 09:48 PM
#7
Former Vendor of MBWorld
Thread Starter
1st, Brabus says that this mod does not set and CEL's off, is this possible replacing all 4 w/ 300 cell cats?
2nd, Brabus says there is some type of special gel coating inside the cats to help with heat, what could that be/where do you think you can get this stuff? Jet Hot maybe?
3rd, Is it reasonable to expect that it will make me approx 9whp coupled with the cat back exhaust?
4th, Since they ask something like 10K for the four 300 cells and the exhaust, and I already have the exhaust, would it make sense to try to replicate this setup w/ universal 300 cell cats or do you think Brabus really knows something that warrants me spending all that extra money?
BRABUS B7
Base:
E350 (W211)
Power enhancement by back pressure lowering metal-catalytic converter (four monoliths with a full
OBD II suitability). The kit is completed by a matching stainless-steel end-muffler.
2nd, Brabus says there is some type of special gel coating inside the cats to help with heat, what could that be/where do you think you can get this stuff? Jet Hot maybe?
3rd, Is it reasonable to expect that it will make me approx 9whp coupled with the cat back exhaust?
4th, Since they ask something like 10K for the four 300 cells and the exhaust, and I already have the exhaust, would it make sense to try to replicate this setup w/ universal 300 cell cats or do you think Brabus really knows something that warrants me spending all that extra money?
BRABUS B7
Base:
E350 (W211)
Power enhancement by back pressure lowering metal-catalytic converter (four monoliths with a full
OBD II suitability). The kit is completed by a matching stainless-steel end-muffler.
1 - Yes
2 - probably just marketing hype
3 - yes very reasonable, the V8s have gotten 10+ easy for just modifying the secondaries, so do to all 4, that seems very reasonable.
4 - Very simple to do, 4 cats will cost you about $350-360, that seems like a massive ripoff, just get the cats on ebay and do it yourself, its very simple. 2.5" cats are probably best for secondaries, primaries you might be able to do 2.25s (since piping is smaller after the headers).
http://cgi.ebay.com/ebaymotors/_Car-...3A1|240%3A1318
Tell that seller you want a set of 4, he will make you a deal for $350 including shipping, tell him you found out about him on the mercedes forums, he's very reasonable.
Those are OBD2 compliant 300 cell metal core cats that are 49 state legal (sorry cali guys).
You could probably get the whole setup installed for $550-600 total if you find a shop willing to do the labor for cheap enough (secondaries cost on avg $300, $180 parts, $120 labor).
Hope that helps,
~AMS~
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03-10-2009, 10:45 AM
#8
MBWorld Fanatic!
Does anyone have any idea how I can expect the car to sound if I replace the stock cats with the 300 cell ones? I should keep the resonator as I want to keep the db level to a minimum no? Does anyone have a similar set up, 300 cell cats on primary and secondary and a high flow cat back they can post a clip of? Any other suggestions anyone might have?
03-11-2009, 02:42 AM
#9
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'03 CLK 55
but these cats mod will still cause CEL to pop out right?
1 - Yes
2 - probably just marketing hype
3 - yes very reasonable, the V8s have gotten 10+ easy for just modifying the secondaries, so do to all 4, that seems very reasonable.
4 - Very simple to do, 4 cats will cost you about $350-360, that seems like a massive ripoff, just get the cats on ebay and do it yourself, its very simple. 2.5" cats are probably best for secondaries, primaries you might be able to do 2.25s (since piping is smaller after the headers).
http://cgi.ebay.com/ebaymotors/_Car-...3A1|240%3A1318
Tell that seller you want a set of 4, he will make you a deal for $350 including shipping, tell him you found out about him on the mercedes forums, he's very reasonable.
Those are OBD2 compliant 300 cell metal core cats that are 49 state legal (sorry cali guys).
You could probably get the whole setup installed for $550-600 total if you find a shop willing to do the labor for cheap enough (secondaries cost on avg $300, $180 parts, $120 labor).
Hope that helps,
~AMS~
2 - probably just marketing hype
3 - yes very reasonable, the V8s have gotten 10+ easy for just modifying the secondaries, so do to all 4, that seems very reasonable.
4 - Very simple to do, 4 cats will cost you about $350-360, that seems like a massive ripoff, just get the cats on ebay and do it yourself, its very simple. 2.5" cats are probably best for secondaries, primaries you might be able to do 2.25s (since piping is smaller after the headers).
http://cgi.ebay.com/ebaymotors/_Car-...3A1|240%3A1318
Tell that seller you want a set of 4, he will make you a deal for $350 including shipping, tell him you found out about him on the mercedes forums, he's very reasonable.
Those are OBD2 compliant 300 cell metal core cats that are 49 state legal (sorry cali guys).
You could probably get the whole setup installed for $550-600 total if you find a shop willing to do the labor for cheap enough (secondaries cost on avg $300, $180 parts, $120 labor).
Hope that helps,
~AMS~
03-11-2009, 12:20 PM
#11
Former Vendor of MBWorld
Thread Starter
No, these have nothing to do with O2 sensors and will not cause CEL at all.
The Car does sound a bit more performance oriented and there is more sound emitted on the top end but its not a huge difference since the primaries are still intact. Headers with high flow cats work really well together. I would recommend doing the high flow cats first, then if you are still not happy after a few weeks you can change the resonator or add headers or whatever. Upgrade in steps in order to prevent going too far.
hope that helps.
The Car does sound a bit more performance oriented and there is more sound emitted on the top end but its not a huge difference since the primaries are still intact. Headers with high flow cats work really well together. I would recommend doing the high flow cats first, then if you are still not happy after a few weeks you can change the resonator or add headers or whatever. Upgrade in steps in order to prevent going too far.
hope that helps.
03-11-2009, 12:21 PM
#12
Former Vendor of MBWorld
Thread Starter
By the way I forgot to mention...
Stock cats were about 5.4 lbs each, the high flow cats were 2.7 pounds each (so basically 50% lighter), so for the pair you get roughly 5lbs in weight reduction. Hope that helps.
~AMS~
Stock cats were about 5.4 lbs each, the high flow cats were 2.7 pounds each (so basically 50% lighter), so for the pair you get roughly 5lbs in weight reduction. Hope that helps.
~AMS~
03-11-2009, 08:42 PM
#13
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'03 clk 500. WTB slk55
03-12-2009, 02:19 PM
#15
Former Vendor of MBWorld
Thread Starter
03-12-2009, 03:05 PM
#16
MBWorld Fanatic!
It depends on the manufacturer. I've personally owned cats where the washcoat (the catalyst material) was useless in 3 years. This was on a car that received a new O2 sensor, and never consumed oil or coolant (either of which will kill a cat).
03-12-2009, 06:32 PM
#17
MBWorld Fanatic!
03-12-2009, 06:38 PM
#18
MBWorld Fanatic!
03-12-2009, 06:45 PM
#19
Former Vendor of MBWorld
Thread Starter
