2013 Mercedes C300, X-Pipe and 2nd cat delete, short drive

A short drive clipped together from my 2013 C300. The center resonator is replaced with a Magnaflow X-Pipe P/N 10790. The 2nd cats (that are not actually cats, just small resonators) are replaced with straight pipe. The stock cats and mufflers are still on the car.

[@HeyboysGarage]

Quick question! I'm not sure if you would know the answer to this since you did an extra step from my question. But deleting just the Small resonators/mufflers. How drastic does that change the volume and sound of the exhaust with everything else stock? Let me know if you have an answer

[@cummins24421]

With the center resonator removed as well it changes the sound pretty drastically. It's a nice growl under normal driving but get a pretty nasty rasp at high rpm/heavy throttle. I don't know what it would sound like with the 2 small resonators deleted and the center resonator still intact, I took mine out in the opposite order.

[@HeyboysGarage]

@@cummins24421 gotcha! I ask because I want to just start with the two small resonator. I deleted the muffler off mine in place with an aftermarket muffler and it sounds great but too loud for my taste and it drones from 70-75mph. So I will be putting back my muffler and try the two small mufflers.

[@imazreal]

@@HeyboysGaragehow did that go for you?

[@jackliu3806]

I’m thinking about doing a secondary cat delete. What did you replace the cats with? Also did you pass emissions with it? Love the sound man. I alr got a res and muffler delete but want some more pops

[@cummins24421]

Just replaced them with straight pipe. They aren't actually cats and don't effect emissions at all.

[@jackliu3806]

@@cummins24421 any check engine lights?

[@HasinShahadArRafi]

@@jackliu3806 theres basically 3 resonators. the primary one and the one that looks like 2 cats. no check engine lights whatsoever

[@jasonb4196]

I have this exact year make and model and tmr I have an appointment to install my magnaflow X-pipe but iam not sure if I want to remove the secondary resonators 🤔???...

[@declancosford7701]

what did you end up doing? how does it sound now?

[@hunterattenborough1754]

Does deleting the 2nd cat cause any problems down the road?

[@cummins24421]

No, it's not actually a cat. It's just a resonator. It doesn't effect emissions, throw any codes, or influence fuel mileage. It just dampens noise.

[@hunterattenborough1754]

cummins24421 thank you for responding I appreciate it!

[@w204doeben6]

My c300 is making a weird thumping sound when I rev it Nd when it’s coming down from the rev it the car jerks a lil bit

[@w204doeben6]

Any one else ?

[@cummins24421]

In neutral as well or only when it's in gear? If it's only in gear, transmission issue. If it's in neutral, probably something like a valve, lifter, or cam problem. Either way, very unlikely to be an easy fix.

[@w204doeben6]

In neutral Nd when I floor it it’s not like hella loud but you feel the shakiness

[@bbking2451]

Do u feel it being a little faster?

[@cummins24421]

No, not at all. It sounds way faster but the actual restrictions, the cats and manifolds, are still there. There's no performance change.

[@wolf0killers]

Are the secondary cats empty from the inside are they like resonators ?

[@cummins24421]

I didnt cut them open, just out. To my knowledge, they are just resonators. Even if they aren't, they dont have any sensors so dont throw a code when they're removed.

[@jonathanwu2190]

Any drone?

[@cummins24421]

Not really. Some slight drone when I'm on the interstate at 80+ but not driving normally. I can listen to music at a normal volume without noticing the exhaust at all.

[@jonathanwu2190]

@@cummins24421 OK, thanks. Cuz It sounds awesome when you hitting the gas, but just wanted to know how was it when driving slowly

[@tarifthoaid1725]

How is it on gas

[@tarifthoaid1725]

How is the car with gas with the x pipe

[@cummins24421]

@@tarifthoaid1725 no change. I get around 19mpg but I live in the DC area so I spend most of my time in traffic. Highway, I've gotten 25+ on long trips up the east coast.

[@tarifthoaid1725]

cummins24421 damn nice I get 14.9 city I live I nj