abramelkyzedeck

Hey guys ive been reading the forum about xpipe vs straight pipe vs cat delete for ages. I actually decided to delete the resonators and replaced them with straight pipes. However i can notice the throttle lag now, especially when you accelerate from a stop. The esp light also keeps on coming when i accelerate real hard. Anyone facing the same issues with a resonator delete? Thanks in advance

SonnyakaPig

I do not have experience with replacing the resonator, but it seems strange that your traction control light is coming on more frequently now that you're experiencing less umph from your engine.

Personally, and this is just a guess, I don't think you are going to affect your power delivery by replacing your resonator with straight pipes. The resonator is far enough down stream that the exhaust flow is pretty much regulated by the exhaust manifolds, primary, and secondary cats, by the time it reaches the resonator.

But, seat-of-the-pants can be a good indicator, so I don't discount your experience, here.

Do you like the change in sound from the mod?

yooker

N/A engines need some back pressure for low end torque.

SonnyakaPig

But torque figures rise for the M156 when you increase diameter of exhaust piping.

_AMG_

FYI deleting resonators will have absolutely no increase or decrease in power.

MBH motorsports

+1

Mostly you just need to reset the adaptations in the ECU from daily driving.

ShaneN.

I don't want to start a thread for fear of getting sh*t on for it, so hopefully someone will take the time to reply to this old thread but I have a question along the similar line...

I see that removing the resonators should make zero difference but how about doing an x pipe where the secondaries are (plus straight pipe reso delete)? Just making sure there aren't any negatives before going ahead with it.

BLKROKT

Holy **** are you serious? Try searching for “x-pipe” genius.

jptaylor

There's my B*tch!!!!! Hell, I've had EVERY iteration mentioned and posted the results of each....

Delete the 2nds and call it a day, if you want more sound delete the mufflers.....or long tube it first thing and forget the rest.

ShaneN.

I searched, it brought me to this thread, hero. I'm not sure if english is your first language but it's pretty clear my questions was more specific to the responsivenss/back pressure with those particular modes as I see to notice a bit of lag with just the reso delete on my new car.

I'd hate to imagine how much your panties would be in a twist if I started a new thread though ...

skratch77

I know what you felt as I lost a lot of throttle response and pedal felt mushy on part throttle acceleration doing full long tubes and no cats at all.

The reason you felt the throttle lag or dullness is because the factory resonator has an h pipe inside it and you definitely lost mid range without it.

jptaylor

You should never delete the reso on our cars....not only is the sound changed in a negative way but YES, there is a lag... But as to your specific question, you answered it yourself the first time you drove your Merc after deleting the reso so in the end you didn't so much want an answer to a question you just wanted someone to confirm your own observations, and this has ALL been discussed in 5 dozen threads before

ShaneN.

Is this something that can be resolved with a tune? It seems like more people have some sort of exhaust work than not. When I test drove my car I thought there was sowmrhing wrong with it but it was clear it was more of a bogging feeling than like a slipping tranny so I'm going to assume that the reso delete is my "issue" too.


edit: I remember seeing a thread where a company called gt pro offered a double x pipe setup to replace reos/2nd cats. Perhaps that would keep the right back pressure and give the desired sound? Eurocharged sells a pre fabbed stainless x pipe. I assume I could just grab two of those and have an exhaust shop weld them up for me. Opinions? http://eurocharged.ca/product/63-ser...ipe-63_x_pipe/

Ambystom01

Why would you go double x-pipe? The issue is that with straights at the resos, there's no crossover anymore. A single H-pipe or X-pipe at the cats would rectify that.

bentz69

When you say you lost throttle response with long tubes and no cats, what was the rest of your exhaust setup? Straight pipes all the way to the mufflers?

I now have long tubes, no cats, resonator removed but a 0.75" H where the resonator was and the midrange is certainly there. The whole powerband is strong. Hard to believe that little H makes such a difference in regards to performance but obviously it does something other that making the exhaust note sound nasty.

skratch77

I lost alot doing an x like the one you are selling (actually same exact one) and the stock resonator together.

When I took that ***** out the car came alive and figured that hpipe made the difference.

bentz69

So you have long tubes, straight pipes into stock reso. I know that little H in the reso is really small. I wonder how the tone changes as you increase the diameter of the H. Ive seen guys on here recommend a 3" H

Celicasaur

Quite surprised about that, as the Weistec/MBH design is pretty much perfect for what an x-pipe would be like for a high revving, big displacement motor like ours. Maybe your issue was down to placement of the x-pipe?

What I can certainly vouch for being an incompatible x-pipe on our motors is the Magnaflow one....don't ask me how I know


The C63 resonator/H-pipe is 2.5"?

Might be worth sourcing one from an E63 or SL/CLS etc....the entire exhaust system on those are 3".

I might be refitting my resonator soon tbh...car sounds too unrefined at the moment.

ShaneN.

That's the answer I'm looking for. Thanks

bentz69

We are talking about the actual crossover pipe that merges the two exhaust pipes. That tiny crossover inside the resonator is very small in diameter. Increasing the size of that particular pipe would change the exhaust note

ShaneN.

Any idea what the diameter of it is? Thinking about having an H pipe either made or retrofitted using the straights that are in position there. I found a thread on h-pipes and two guys chose 1.5" for the connecting piece but it seems like it was just a random number they were choosing.

bentz69

The oem size is about 1/2 inch diameter. I have a 3/4 inch diameter pipe in the same place where the oem resonator has its crossover. I'm wondering what a larger pipe would do....

Celicasaur

My apologies, what I meant was that the inlet/outlet of the resonator unit would be around 3", which is what I assume most people run as the diameter of piping for their exhausts after getting headers fitted. I'm sure the internal H pipe is the same as for the W204 model or slightly bigger