barnabas

hi guys, sorry i havent got the chance to post the pic of my car.. anyway.. i did the resonator removal and put the x pip today.. the noise was great but not ythat loud enough.. do you guys think it is wise to take out the secondary catalytic converter too to make it louder? thx for the comments guys and i hope this will be helpful to others wondering too.

alroumi

Hello,

I've done exactly what you want to do last year and replaced my secondary catalytics with a pair of 3" Race Kleemann 200 cell catalytics and it sounded much better, honestly it should of come like that from Germany as the stock version is kind of weak.

Here is a video,
http://youtube.com/watch?v=frHg9dFUG24

IIIMBPIII

Oddly enough I went to the muffler shop the other day and I was asking would it make a difference in sound he said it wouldnt make much. He aslo went on to say that the newer CATs from the factory are pretty damn good is this true? I kinda wanted to take it off just for the hell of it. Car sounds great as always Moh!!!!

alroumi

Not true the most restrictive parts of the M113 are the exhaust work and air intake, the only thing which I find good are the oem mufflers.

Have you looked at my thread on SLK world, I showed the difference between the oem headers and the Kleemann ones. The oem front set of cats are extremely restrictive.

spr

Are you sure about that? Another member changed the headers did a dyno then decided to do a full custom exhaustfrom headers back. Dyno gain was 2-3hp- It is widely known the manifolds are terrible but everything else is sufficient.

IIIMBPIII

Damn it see I should always listen to you guys! Im going to take off the post cat this weekend then when I get the the new headers I will replace the post and primary CATs with maybe Magnaflow racing CATs. Oh I got my new rims Moh but when I went to put them on turns out I didnt have the right lugz which we found out by taking all the stock wheels off putting the tires on the new rims and mounting them I was so angry!

alroumi

Sorry to hear about this, in regards to the catalytics I always stay with the tuners.

I've only got the best and those are european tuners, I followed the Kleemann S8 setup but I found out that the resonators are not needed so thats why I went for SuperSprint x pipe to improve flow when combined with the Kleemann 3" cats.

IIIMBPIII

Did he tune his car after all was done? I hear that if you dont you may not gain the full potential of the mods

alroumi

I agree a tune is the best thing to do after a owner has full bolts ons, as the car is now programed to understand the new upgrades and improve air and fuel ratios.

barnabas

so basically i should replace the cat with like a kleeman cat or magnaflow cat? how much does the magnaflow and kleeman cost? anyway i live is sf bay area too so maybe we could hang out sometime.. some of my friends use amgs and M , ill be great to hang out

IIIMBPIII

Awesome we should deff meet up Im always looking for people in the area to hang out with that love cars PM and we will swap info! As for the CATs Im assuming the Magnaflow will be a lot cheaper than Kleemann and im sure some people will tell you to go with Kleemann cause they are a Merc tunner but I've found in the past that Magnaflow makes very good products and I used them on my BMW with better results than other tunners. I dont know to much about CATs Moh would know more he has Kleemann and he loves it. When I get my headers I might go with Magnaflow to check them out maybe not we will see.

IIIMBPIII

You should also add yourself to this list for future meets and gatherings!

http://mymbonline.com/forum/viewtopi...er=asc&start=0

SLK55R

Just make sure they put in the O2 sensors at the cats.

I didn't want to mess with it so I just went with full Supersprint exhaust ...minus the mufflers.

alroumi

The Kleemanns cost around 380 dollars if memory serves me right.

barnabas

hmmmm so basically do i need the headers too or can i just have th kleeman or magnaflow cat to improve the sound of the muffler? i do not really care about speed increase since it will not affect much but i want the sound.. and if i just got the kleeman or magnaflow cat, what about the o2 sensor.. anyway thx for the help guys

alroumi

You dont need headers, thats what I did a year ago before I purchased headers.

So basically the guideline is to have

The front two oem catalytics........................Secondary Afterkarmet catalytics ( magnaflow/ kleemann)...running down to the ( X pipe/ resonator delete) and then through the oem mufflers.

barnabas

ooooo hahaha ok2 that makes it much clearer.. thx! but hmm i need to keep the seconday cat too? u are saying keep oem primary and secondary cat.. and add the kleeman cat? there is only 2 cat right? i though i need to replace the secondary cat to the kleeman cat

barnabas

hi guys and 2 more thing, first does anyone knows where to buy them? either kleeman or magnaflow and second is whether it is ok if i just ake the cat a straight pipe without using any kleeman or magna cat??

IIIMBPIII

What I believe Moh is saying is leave the primary CATs stock which are located up but your headers these have O2 plugs running into them and replace the secondary CAT with either Kleemann or Magnaflow!

alroumi

Correct, your a good learner

You can get them from many vendors, It depends on your location. If you have provided it under your username I could of helped you find one as I find it better to purchase localy than from a further state were you might pay a lot for shipping, insurance and tax.

IIIMBPIII

You will need primary cats due to the readings from the O2 sensors if you remove those and just run straight pipes your car will be RIDICULOUSLY loud but you will also have the CEL (check engine light) come on. As for the secondary im a little confused when I talked with my Magnaflow guy about just removing the secondary CAT and replacing it with a straight pipe that it wouldnt make much difference in sound. Is this true anyone? Now where to buy, Im sure there are places up near you that sell Magnaflow try and find a reputable muffle shop and talk with them. Worse comes to worse you come to Marin and I hook you up with my guy. As for the Kleemann either you could contact them directly or I think many tunner companies could order them for you. Ask Moh about that one im not really sure!

alroumi

You cannot run the car without the 4 catalytic converters, as it will directly run on limp mode. The Kleemann catalytics can be purchased through any Kleemann retailer in America, you can start of by checking out www.kleemann.de , NA region and find the closest shop per state.

You will definatley not get a checkengine light if you replaced your oem secondary cats with aftermarket one's, if you delete the fronts and do not flash your ecu then your into trouble if you are not going to re route your 02 sensors to the back of your secondary catalytics.

Basically you should be fine if you plan on removing the resonator( I dont suggest straight pipes go for the X-pipe as it sounds better and not like a Harley V-Twin ).

IIIMBPIII

So just to clear everything up if I just removed the secondary CAT and replaced it with a straight pipe for the time being would that increase or change the sound in anyway?!

alroumi

It will sound extremely loud assuming you have removed the resonators and will drone badly which isnt good. Instead of it sounding like a proper 5.4L German V8 it will sound probably a bit too raspy for an average motorists liking whilst installing your soon to have headers will cause a cel since you dont have secondary cats due to removing the front set of cats for the headers and its downpipes.