Removing Cats - Also, best exhaust shop?

[KPHMPH]

So I'm toying with the idea of removing he 2 cats on the ML63 ( 2008 ) and was wondering if I will be running into many problems with the computer from previous people's experience.

If I go ahead with it, which shop (s) are the best for quality of work and price.

[benz_890]

Minute Muffler 32 Ave

[BokCh0y]

Mine was removed on my Tacoma, but that was because someone jacked it. I had carline on mcleod trail and 58th repair with a straight pipe.

So far, haven't noticed much of a difference in power. A bit of exhaust in the truck though...weird.

[StreetRacerX]

I'd go with Ravi at Minute Muffler 32nd Ave NE unless you want exhaust porn, in that case Chris with Unobtainium Welding

[revelations]

Originally posted by BokCh0y
So far, haven't noticed much of a difference in power. A bit of exhaust in the truck though...weird.

Same here actually, had Ravi do a full system in my car (cat delete, supplied my own header, 3" pipe) in the winter but started to notice exhaust in the cabin with the sunroof open once spring/summer came.

Nothing obviously wrong - otherwise exhaust sounds awesome!

[Projek01]

Your car will throw a CEL for catalytic converter below efficiency threshold. Of course some cars are more picky about it and maybe you will get lucky. It is definitely not worth the trouble unless you have a aftermarket tune. The reason is that that would allow you to disable that error code.

Now that environmental side of things also goes into play. The cat is in there to reduce the amount of NOx emissions which is a large contributor to smog. Is the 0-10hp gains enough to justify your added contributions to the smog everyone breathes in?

[klumsy_tumbler]

Originally posted by StreetRacerX
Chris with Unobtainium Welding

[revelations]

Originally posted by Projek01
It is definitely not worth the trouble unless you have a aftermarket tune.

That is an incorrect, generalized statement. Some cars (eg my lowly civic) get about a 5-10% bump in HP after cat delete, without a tune.

Its HIGHLY dependent on the specific vehicle however.

[zieg]

Very few cars have such shitty stock cats that you'd get 5-10% and forgive me but on a civic that's still only like 15whp if memory serves?


The fact that you're asking makes me want to say no. Some cars can be fooled with o2 extenders, many others can't. Then you have to live with the check engine light always being on and never knowing if it's only on because of that, or if another problem has occurred.

I'm any case, if your cats aren't clogged, and you're not frequently racing on a track, there's really no reason at all to remove them. On the street you will never feel the power difference (barely notice on a dyno) and only on a track is there any serious danger of burning them up.

[Hallowed_point]

I wouldn't do it to another street car after having two cat less V8 cars. Between the smell, check engine lights and added pollution it's not worth it from my experience. Ever get stuck behind a cat less car? It can be pretty nasty. Plus your clothes start to stink of exhaust. Cat less can sound pretty good on some cars, but I still wouldn't do it again.

[Sentry]

ML63? Fucking do it man. Those things sound amazing uncorked.

[revelations]

5-10hp is noticeable street gains for a vehicle (like my civic) with less than 180hp stock. Many EP3 discussion groups had topics about how owners were surprised at the instant gains. I was replacing the entire exhaust system anyway so it wasn't a huge decision to dump the cat.

Having said this, I would not do this to my V10 F250 as the pain would outbalance any gains - according to the owners discussion groups anyway.

OP read up on the requirements for your MB.

[KPHMPH]

So after doing a bunch of digging on the subject I've found it so increase the sounds ( which I want ) but not increase them enough to make it sound horrible. I don't want to replace the muffler because you will start to get some bad drones in the cabin at highway speeds ( we do a lot of kms on the highway with road trips )

So today the ML went in just to remove the cats and put 2 straight pipes there. Leaving the stock mufflers in and we will see how it sounds.

[rvd]

Bump post update on sound, good or bad ?

[BokCh0y]

Mine's a bit louder without the cat for sure, but not anything on the line of sounding like a grapefruit launcher. I personally like it.

[KPHMPH]

Good sounds! No drone at highway speeds but a throaty startup and WOT.

[Redlined_8000]

Your ml63 should have 2 sets of cats anyway. Primary and secondary. You can remove the secondary cats without any negatives at all. Should give 10hp extra and make the exhaust a bit louder.

Stock muffler on the m156 is already very free flowing and loud. The cats and stock header is what restricts alot of the noise. If you go for long tube headers with stock muffler it will be very loud.

[cancer man]

Don't do it you will notice noise but no power untill upper rpm zone.
I'am telling you that it will be a big regret.

[shakalaka]

I had my c63 straight piped. Believe it was the secondary cats that were removed. It sounded pretty mean.

Which shop did you end up using?

[rx7boi]

Neat, how much would a job like this typically cost at 32 Ave Minute Muffler?

I'm thinking about getting an o2 housing installed and going turboback again.