Just got Modalworks installed by SSR Performance last week. Tuner (Gintani) went overboard on the rice krispies! Also have ZAC intakes.

 

Just an update Got the big daddies spacers installed on my car and they cleared up the check engine light from the modalworks downpipes and there has been no issue so far, if it keeps up I will assume that it fixed the problem as It did for the others prior to me.

 

What scan tool are you using?

 

using Auto Doctor app on iPhone with a BT OBD connector.

 

so I have the Modal Catted DP and the Big Daddies spacers and my shop (they have done several W205 DP, just not Modal) and they cannot get one side in. Any ideas? This is what they sent me:
"One thing we wanted to let you know is that the O2 Spacer you provided us does not fit with the limited spacing around the mid-pipes. It is physically impossible to make it fit as it hits a coolant line without the O2 Sensor even installed. We're assuming the forums that you've read must have an aftermarket exhaust or modified their exhaust as there is no way to make these fit."

 

So this is what the shop sent me as to the spacing and coolant line. I don't know how you guys were able to get it to fit.

I don't know if there is value in running one spacer at this point, just frustrated that after going with catted DP and getting the spacers, still have issues.

 

Pics attached.

 

hey man sorry to hear your having problems, unfortunately I did not have the same issues when installing the spacers at least my shop never mentioned any kind of difficulty to me. Took them less than an hour, modalworks reached out to me and I’d be happy to try and get a picture of how mine are but I’m currently getting the car wrapped and won’t have it back until Monday.

 

So it looks like the O2 sensor is off center from the hard coolant line, whereas on mine it is pointing right at the coolant line.
My shop said that the DP are typically made on a jig, so a little variance on how it is secured could put the bung on a different angle or position.
The other possibility is that my coolant line is different - I have a 2020 C63S, what year are yours?
Regardless, the CEL was off for the drive from the shop to the dyno, but when I had it put on the highway, CEL on. Annoying.
Did pre and post dyno with intake and DP, no tune. The intake gives a wicked induction sound, might even grab the Eventuri CF ducts. Hope to have maps tomorrow. The shop is in the process of transitioning to a new location, hence temp appearance.

 

What were the numbers on the dyno ?

 

there is no agency who will turn down a trade if you’re ready to move forward with a vehicle they have over catted DP’s. If you’re private selling and decide to advertise that you have catted DP’s then you sell as is and someone will bite

 

Not sure of the other guys, but my priority all along was improving the exhaust sound of my FL C63S, while maintaining warranty and emissions. Coming from a W204 with secondary cats removed to a FL W205, part of the fun of the car is gone without the muscle car noise. It is like having a taco, but get unseasoned beef and no salsa or cheese. And just cutting out the cats/particle filter does not seem straightforward.

The reason for the dyno was not to try to see how much power I gained, but just curiosity to see what happened when I did both DP and intake. Also, it was easy because the same shop that did the install did the pre and post dyno, and cut me a deal. If I was out to maximize power, I certainly would be doing it in conjunction with a tune, but I just wanted to make the car more fun.

They have not sent me the graphs from last night yet, but should have them soon. From memory, I gained about 20 HP and 20 Tq in midrange around 4-5K rpm, but decreased to about 10 near redline. Lower down the graphs were almost identical.

But, this is what it was for -

 

What you did is exactly what I want to do so the dyno is very helpful. I don't want to do a tune just yet and want to do catted downpipes and intake only.

What gear did they dyno in? Did the car build full boost down low?

 

I got my 2020 c63s coupe 2 weeks ago.
Although I am still doing break in, I ran the car carefully few times in Sport+ mode with Renntech EVM (full open mode) and car is not as loud as I wanted it to be.
According to some other post, 2019+ models should be making more pop and crackle noise after few thousands miles, but not sure if exhaust volume is going to get any louder too.
If not, I will most likely get catted DP with O2 spacer and run it without tune.

I was considering Modalwork catted DP but Spazdoc’s post is making me look for other solution.
I did some research and found Shardul’s DP offering with Gesi cats might be good choice.
Unlike most catted DP, his has Gesi cats installed on further down the pipe where original secondary cats are placed.
Also, O2 bung location is moved to accommodate new cat location.
I think by having O2 bung moved down, there is going to be much more free space allowing easy install of O2 sensor with spacer.

Well, I am going to drive my car for few thousands more miles to see if my exhaust wakes up. Hopefully, it will.

 

Congrats on the new pick up! Can you share the website you can buy these from? I haven’t seen any downpipes with the cats at the end. These look like they would pass the visual portion of a smog test.

 

Thank you! Yes, passing visual inspection is plus for this setup.
I don’t think this is available to purchase from website but you can PM shardul directly for inquiry and purchase.
https://mbworld.org/forums/members/84044-shardul.html

Other donwpipe that has similar setup is IPE downpipe. But not sure if you can purchase this one anymore.

 

I don't believe those downpipes, with the cat located in the secondary (lower) location, will keep you from throwing a CEL. The removal of the primary cat is what will throw the CEL. I believe the inclusion of the lower cat is more for reducing the odor you get with catless downpipes.

 

That is correct. Any downpipe with high flow performance cat in any location will throw cel. That’s why you have to use bigdaddy mini-cat spacer to eliminate cel.
But having high flow cat in secondary cat location instead primary will most likely let you pass California smog visual inspection... but that’s something I only have to worry after 8 years.

 

I had 2k miles on my 2020 C63S and only did the ASR to keep flaps open. I did not get any pops on downshifting. After install of the DP, the exhaust is much deepr and a little rapier, pops are coming in in S+ mode, and it just sounds soooo much better (yesterday I drove 45 mins out of my way just to drive the car because it sounds so much better). Actually, not quite as intoxicating as my W204, but perhaps as good and loud as I want given the turbo setup will never sound like the W204.

As the issue is the hard coolant line, I doubt the location changed significantly from pre-FL to FL, especially since there is limited space as it is for the O2 sensor. I suspect that it is more likely that there is variation in the placement of the sensor bung on the DP. As there is heat shielding, I was hesitant to just weld and cut into the DP, they there is a potential solution.

Modal wasted no time contacting the other catted DP owners on their situation, and so I hope that the figure out an option to relocate or reposition the bung enough to allow the spacer to work. They can also just say that it is my own bad luck (either changed coolant line location of bad bung placement), as the position of the bung allows for placement of the stock O2 sensor. This would be a bad argument, since the entire reason why a C63 owner goes to the trouble of paying extra for catted DP and then sourcing separate spacers is to avoid CEL, pass emissions, without the ramifications of doing a tune (a simple O2 sensor delete will not pass emissions). It took only a couple days for another owner to already jump in say that they will go with a different manufacturer, and it is likely not the last. Furthermore, many manufacturers have to have a FL update, if this is the case.

I have faith that Modal will try to figure it out, and I have confidence in my shop with working with me if we need to swap things out - if anyone is in Chicago area, make sure to check out Performance Eurowerks.

 

i used to think the same like you when i had 2k miles, it actually changed drastically above 5k mile. just wait and drive hard until then... keep warming that exhaust ^_^

 

2019 c63s coupe. had heavily debated catted vs catless, but ended up biting bullet and going Capristo catless dp and weistec stg2 tune. Def woke it up, much louder, more pops, etc. Seems to be coming into itself a bit as time goes by. Sound seems be getting a little better as things as getting broken in and whatnot.
I get more pops when driven hard for sure. I have no added burble on my tune at all. Im sure it would be enough for some ppl and not enough for those that are really into it. Im probably going to get an addl file from weistec with level 1 burble added. They have 0-1-2-3 level of burble. Currently I get pops on like maybe every 2nd to 4th lift off pedal when over 3-4k rpm. Upshifts are mean. In park i get pops about same every 2-4 good rev ups.
Id like to have just a tiny bit more, which is why gonna try a lvl 1 burble. Itd be great if could have them map burble to just S, S+, or Race so could have it when i wanted and normal when I dont. I know too much burble is bad for longevity of turbos etc.
I know this is catless but maybe help some of you.

 

Oh please give an update when you go with the level 1 burbles. I have the Weistec Stage 1 tune with burbles right now (not sure what level) and feel like it’s too aggressive even though I already asked them to tone it down a bit. I have the HJS 200 catted Red Star downpipes coming in so I’m considering either deleting the burble tune or going with level 1 when I get the downpipes installed and retuned.

 

When u do ask them what lvl burble you have.
also what year do u have...facelift or pre ?

 

I have the Facelift (2019) what about you?

 

Same 2019 c63s coupe.