mikeyyyallday

can someone explain to me what this means….and does it need to be replaced with something or not? can any local exhaust shop do this job?

AMG893

Yeah, any exhaust shop can do this.

It will be removed, and replaced with a normal pipe.

alpharabbit

https://mbworld.org/forums/c63-amg-w...uy-thread.html

Secondary cat delete removes the cats halfway between the engine and exhaust tips. It needs to be replaced with either a straight pipe or h-pipe or something. Take a look at the thread for more info and also a fantastic option in purchasing the replacement pipe. Mike makes quality parts.

ruey220

i posted about this in the following thread.
https://mbworld.org/forums/6026665-post13.html

mikeyyyallday

anywhere else that sells quality pipes? mike might be out.

intence

save your money and just go to a muffler shop for $200 lol

estrellajon

Will removing the secondary cats and straight pipe cause a CEL? Will it pass state inspections?

Ingenieur

It probably will
Iirc the ecu compares O2 sensors and since it won't see a difference since the cat is gone

If your state does a visual emission inspection you may get caught
You may also fail the sniffer
They are there for a reason

imo the car will run better and more efficiently with them

estrellajon

My state does OBD. If it shows CEL or not ready then won't pass.

intence

you wont get a CEL with secondary cat delete. i wouldnt worry about emissions because its obd2 testing and because secondary cat delete is not loud enough to raise any eyebrows. a visual is another story but do they really look on an otherwise stock looking car?

Ingenieur

Why no CEL?
If both sensors see the same O2 won't that indicate the cat is not functioning?

Don't folks have it programmed out?

But it still is trying to trim the mixturep

dubzAMG

No cel because the secondaries are after the post cat oxygen sensors

Ingenieur

Don't our cars have 4 sensors
A set after the primary and a set after the secondaries?

dubzAMG

Yes they do have 4, the post cat sensors go after the primaries.

Ingenieur

Thanks

BiturboSF

Deleted mine with straight pipes in place for only $70 at a local exhaust shop

mikeyyyallday

does it make a significant sound difference compared to stock?

intence

yes, but only if you get on the throttle. otherwise its as quiet as stock when cruising around. hands down the best bang for buck mod you can do.

estrellajon

No visual at all. They only care about is OBD systems passing. They used to do sniff and visual years back but not anymore.

If there are no sensors after the primaries then possibly no CEL. Are there some gains or just for pissing off neighbors?

sytfu_colan

Which shop did you go to? I want to get it done too. Did you replace the resonator and secondary cats or just one of them? PM if you don't want to reply here.

Did you own an ISx50? Your username sounds very familiar.

avery.whss

this is with just 2nd cat delete revving to like 2500-3000 rpm .. it's mikes straight pipes ..no CEL but it's loud as hell when you get into it

Kriston

H Pipe the cats + Straight piped resonators and the car sounds like a beast no CEL's.






As others have mentioned, its a nice mod for a relatively low price.

Don't waste time with power pipes, go to a reputable muffler shop and have them do it for you for less then half the price!

Mikegpr03

Hello gents I currently have 2 units

Yes you can go to a shop and get a $70.00 job on your 60K car
You will get regular aluminized pipe ( not OEM quality ) and it will have regular bends as well ( kinks ).

I make stainless steel same grade as OEM with stainless Vands so you bolt on and off for such issues as inspection / off road use.

Hope this help

End of the day if you don't care what goes on your car then it's your call.
You get what you pay for.

mikeyyyallday

will replacing second cats with straight pipes require a retune? my car is velos tuned.

avery.whss

no