Question on Cats or Catalysts pls?
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From: CA, NV, CO
Question on Cats or Catalysts pls?
I'm in the process of getting headers/downpipes etc and was wondering if it is advisable to completely remove the primary cats? Will this pass the smog emmision tests etc? Any downside to this? I know it will give me more rumble which is what i'm looking for the from what i understand from Kleemann maybe gains of up to 64hp and 70lb/ft torque. How would this affect the secondary cats or will it? Also which ECU chip should i go for? Kleemann or a Custom Powerchip? Or are they about the same? I'd like to get your opinion on this pls.
Thanks
Thanks
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From: West Coast, USA
2 SL with every Brabus mods available & Class A competition sound system
Originally Posted by JamE55
I'm in the process of getting headers/downpipes etc and was wondering if it is advisable to completely remove the primary cats? Will this pass the smog emmision tests etc? Any downside to this? I know it will give me more rumble which is what i'm looking for the from what i understand from Kleemann maybe gains of up to 64hp and 70lb/ft torque. How would this affect the secondary cats or will it? Also which ECU chip should i go for? Kleemann or a Custom Powerchip? Or are they about the same? I'd like to get your opinion on this pls.
Thanks
Thanks
. Leave it alone.. 
...It not worth it. It little gains in hp and will not pass the smog emmision . Everybody have their opinion 
but for me it not worth it. Cats leave it alone, if you have to get ECU chip go with Kleemann....Good luck....
Out Of Control!!
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haters crazy
Those gains seem pretty outrageous and I doubt it will pass smog. In Maryland a car without cats will definitely fail emissions, and Cali is supposed to be alot stricter. Do they check your emissions through the OBD or tailpipe? If its OBD I think theres a way to pass by some kind of wiring trick (run the secondary O2 sensor wires into the primary or some crap like that), i'll find out more if you are interested in that.
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Out Of Control!
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From: CA, NV, CO
SL BRABUS: Thanks for the reply. Although i need to do more homework on this just because it might be worth it for me.
blackbenzz: Thank you also for your reply. From what i understand from Kleemann it will pass the smog test although the visual part checking may not. Again will do more homework on this. And you are correct emssions here in cali are much more stricter. I believe for this one it goes through OBD.
blackbenzz: Thank you also for your reply. From what i understand from Kleemann it will pass the smog test although the visual part checking may not. Again will do more homework on this. And you are correct emssions here in cali are much more stricter. I believe for this one it goes through OBD.
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Joined: May 2004
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From: Richmond Hill, Ontario
2003 E55 AMG
JamE55,
I was looking at doing the same thing as you and had the same question also.
I was worried about removing the cats immediately after the headers for fear of causing Check Engine lights. I wasn't too worried about the emissions part becuase I know our cars have pretty efficient motors and in Ontario the smog laws aren't as strict as Cali.
If you find out anything more on this topic, please post.. I would be very interested in hearing the results also.
Thanks!!
I was looking at doing the same thing as you and had the same question also.
I was worried about removing the cats immediately after the headers for fear of causing Check Engine lights. I wasn't too worried about the emissions part becuase I know our cars have pretty efficient motors and in Ontario the smog laws aren't as strict as Cali.
If you find out anything more on this topic, please post.. I would be very interested in hearing the results also.
Thanks!!
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From: SFV, Ca.
W210, W220, W163, W164, C6
James,
I recall on the dynojet, I yeild an extra 4-5rwhp by removing the secondary cats on the NA E430 (no check engine light), I'm sure much more can be accomplished on a force induction "monster" vehicle like yours. The rumble as you stated & the extra weight shaved is well worth it for me...don't have to worry for smog til next year tho.
A custom Powerchip software is ideal since your local and any needs can be conveniently addressed, but at what cost? They quoted me $1500 for tuning a custom software for FI or N20.
But, I may go all Kleemann if I were U...ecu, header/downpipes, wheels, brakes, LSD, PCP - the total package!!! to scare the sh*t out of the next E60 M5 that pulls next to you at the stoplight. 
I recall on the dynojet, I yeild an extra 4-5rwhp by removing the secondary cats on the NA E430 (no check engine light), I'm sure much more can be accomplished on a force induction "monster" vehicle like yours. The rumble as you stated & the extra weight shaved is well worth it for me...don't have to worry for smog til next year tho.
A custom Powerchip software is ideal since your local and any needs can be conveniently addressed, but at what cost? They quoted me $1500 for tuning a custom software for FI or N20.
But, I may go all Kleemann if I were U...ecu, header/downpipes, wheels, brakes, LSD, PCP - the total package!!! to scare the sh*t out of the next E60 M5 that pulls next to you at the stoplight.
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From: SFV, Ca.
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Originally Posted by ahopeter
Jam, you wont pass... i did it and failed. dont bother, gains are minimal and i have even experienced torque loss on the low end. trust me, dont bother.
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From: nj
a car that can't do the throttle reset.
Originally Posted by Richard023
Enlighten me, cuz I find it difficult to believe that the gains will be "minimal" with Jam's vehicle. Add the Kleemann kompressor to the mix and you can easily exceed the flow potential of the factory exhaust manifolds. As power increases with the use of the blower more air is added to the cylinder, thus after combustion this added cylinder pressure must escape in order to make more power. A "cork" in the system will only limit airflow exiting the system.
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From: SFV, Ca.
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Originally Posted by ahopeter
how about you relax. i told him my experiences with cat removal in my car. many others that i know have also had the same results. thats what i am going off of. is that good enough enough for you?
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Out Of Control!
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From: CA, NV, CO
Originally Posted by Richard023
James,
I recall on the dynojet, I yeild an extra 4-5rwhp by removing the secondary cats on the NA E430 (no check engine light), I'm sure much more can be accomplished on a force induction "monster" vehicle like yours. The rumble as you stated & the extra weight shaved is well worth it for me...don't have to worry for smog til next year tho.
A custom Powerchip software is ideal since your local and any needs can be conveniently addressed, but at what cost? They quoted me $1500 for tuning a custom software for FI or N20.
But, I may go all Kleemann if I were U...ecu, header/downpipes, wheels, brakes, LSD, PCP - the total package!!! to scare the sh*t out of the next E60 M5 that pulls next to you at the stoplight.
I recall on the dynojet, I yeild an extra 4-5rwhp by removing the secondary cats on the NA E430 (no check engine light), I'm sure much more can be accomplished on a force induction "monster" vehicle like yours. The rumble as you stated & the extra weight shaved is well worth it for me...don't have to worry for smog til next year tho.
A custom Powerchip software is ideal since your local and any needs can be conveniently addressed, but at what cost? They quoted me $1500 for tuning a custom software for FI or N20.
But, I may go all Kleemann if I were U...ecu, header/downpipes, wheels, brakes, LSD, PCP - the total package!!! to scare the sh*t out of the next E60 M5 that pulls next to you at the stoplight.
Thread Starter
Out Of Control!
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From: CA, NV, CO
Originally Posted by ahopeter
how about you relax. i told him my experiences with cat removal in my car. many others that i know have also had the same results. thats what i am going off of. is that good enough enough for you?
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a car that can't do the throttle reset.
Originally Posted by JamE55
Thanks for the input on your experience ahopeter. That is really interesting you didn't pass. I was told that it should be no problem. I might experiment and do this just for the heck of it. But again we'll see. Thanks again for your input!
and some places dont check emissions on the ml... find out if your state does or not. good luck with it, let us know how it goes.
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From: S.F. Bay Area, CA
'18 E63S AMG
Originally Posted by JamE55
Thanks for the input on your experience ahopeter. That is really interesting you didn't pass. I was told that it should be no problem. I might experiment and do this just for the heck of it. But again we'll see. Thanks again for your input!
I don't have any experience with the E55, but when I took the Cats off my Porsche, it actually ran worse on the low end. I guess they created the proper back pressure for low end. With a turbo, I don't believe you need the back pressure, but I'm not sure about a supercharged engine.
Incidentally, the Porsche certainly didn't pass emissions with the CATs off. It didn't pass emissions with the CAT on and a performance chip either.
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a car that can't do the throttle reset.
Originally Posted by CALBenzo
I'm not sure whether a CAT is legally required, or is just generally necessary to bring the emissions down to the state accepted level. If the latter is true, and the E55 could easily pass emissions without it, I'm sure they would eliminate it.
I don't have any experience with the E55, but when I took the Cats off my Porsche, it actually ran worse on the low end. I guess they created the proper back pressure for low end. With a turbo, I don't believe you need the back pressure, but I'm not sure about a supercharged engine.
Incidentally, the Porsche certainly didn't pass emissions with the CATs off. It didn't pass emissions with the CAT on and a performance chip either.
I don't have any experience with the E55, but when I took the Cats off my Porsche, it actually ran worse on the low end. I guess they created the proper back pressure for low end. With a turbo, I don't believe you need the back pressure, but I'm not sure about a supercharged engine.
Incidentally, the Porsche certainly didn't pass emissions with the CATs off. It didn't pass emissions with the CAT on and a performance chip either.
and a porsche with a chip shouldnt fail inspection. i also own a turbo, with many mods and havent had issue with inspection.
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From: S.F. Bay Area, CA
'18 E63S AMG
Originally Posted by ahopeter
its legally required. some dealers wont allow a car to leave if they see it is missing a cat.
and a porsche with a chip shouldnt fail inspection. i also own a turbo, with many mods and havent had issue with inspection.
and a porsche with a chip shouldnt fail inspection. i also own a turbo, with many mods and havent had issue with inspection.
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From: Southern California, USA
2003 CL55 AMG
Originally Posted by blackbenzz
Do they check your emissions through the OBD or tailpipe?
In California they use the Tail pipe probe. They stick a probe up the pipe to sniff the emmissions.
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Originally Posted by JamE55
Thanks Rich! But how about also removing the primary cats themselves? Would i still pass and at the same time be smog legal? I'm not sure on this one so i'm still doing my homework. And you're right. I should have a lot more if not more since i have the s/c. Who quoted $1500 powerchip direct or another shop? I was quoted $1950 since i have a different setup. But from what i understand from Kleemann is it's best to do all the engine upgrades first then top it all off with the Ecu after. You're right i might just do the whole Kleemann deal. We'll see.
I agree, I couldn't stress enough the importance of doing your homework as I'm currently doing for my next engine performance upgrade. Recently, I've seen some hack-job done by a reputable 90210 based tuner
Joel @ Powerchip quoted me the price and Jesse was to do the software upgrade, I'm sure your set-up involves more labor tuning hours...hence the extra cost.
Granatelli Motorsport is a local tuner shop that has done some comprehensive hardware upgrades & software tuning on FI benzos, you may want to contact them. Also, check with Cargraphic I've seen a complete exhaust on a W220, looked promising.
side note: Here in So Cal sometimes the "monetary waiver method" get you better results...
Good Luck.
Last edited by Richard Galing; Aug 18, 2004 at 12:43 AM.
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Thank you all for your input. I'm still looking more into this and will let you guys know what i end up with.
ahopeter: Thank you again.
CALBenzo: Thanks for the input.
Awiner: Thanks bud
Rich: You'e absolutely right about the kleemann. And they don't have any OE# that's why they're only goof for off road use only. This is where the dilemma begins right here no OE#. So i'm trying to find out if there are other alternatives to this if not then i may just skip it.
The guy i talked to was Travis @ Powerchip and yes mine will be a little or a lot more different since i have a totally different setup. But we'll see.
Thanks again all!
ahopeter: Thank you again.
CALBenzo: Thanks for the input.
Awiner: Thanks bud
Rich: You'e absolutely right about the kleemann. And they don't have any OE# that's why they're only goof for off road use only. This is where the dilemma begins right here no OE#. So i'm trying to find out if there are other alternatives to this if not then i may just skip it.
The guy i talked to was Travis @ Powerchip and yes mine will be a little or a lot more different since i have a totally different setup. But we'll see.
Thanks again all!
