Header Related Questions I cannot find the answers for....
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
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From: Markham
07 Z06, 2011 c63pp
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
The MBH headers have rear O2 bungs that the stock rear O2s will reach and that is how mine are installed. The high flow cats in mine have a tube for the rear O2s to be installed but the stock sensors will not be long enough and extensions will be required if you want to use these sensor locations. Since we do not need ready monitors set here for inspections I just had EC tune off the rear cat MIL and it has been working fine. You will be able to use the rear O2 bungs to get started and turn off the MIL in your tune. Or live with any CELs that come up until you can get some extensions and move the rear O2 sensors behind the high flow cats and hopefully any codes will extinguish themselves.
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From: Denham Springs,LA
'12 C63 Black Series, '12 ML350 BlueTech
Either way you do need 02 extensions since your pre-cat sensors are shifted a little bit more downward the path. Therefore your OEM harnesses might be too short.
And yes you would need 2 extensions. One for each bank.
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From: Burke, VA
2014 C63 AMG 507
You will not need O2 extensions but will need the CEL turned off in the tune you install. If you need the readiness monitors set for inspections you may need a workaround of some sort that may require relocating the rear sensors behind the seconday cats. In this instance O2 extensions will be required.
The MBH headers have rear O2 bungs that the stock rear O2s will reach and that is how mine are installed. The high flow cats in mine have a tube for the rear O2s to be installed but the stock sensors will not be long enough and extensions will be required if you want to use these sensor locations. Since we do not need ready monitors set here for inspections I just had EC tune off the rear cat MIL and it has been working fine. You will be able to use the rear O2 bungs to get started and turn off the MIL in your tune. Or live with any CELs that come up until you can get some extensions and move the rear O2 sensors behind the high flow cats and hopefully any codes will extinguish themselves.
The MBH headers have rear O2 bungs that the stock rear O2s will reach and that is how mine are installed. The high flow cats in mine have a tube for the rear O2s to be installed but the stock sensors will not be long enough and extensions will be required if you want to use these sensor locations. Since we do not need ready monitors set here for inspections I just had EC tune off the rear cat MIL and it has been working fine. You will be able to use the rear O2 bungs to get started and turn off the MIL in your tune. Or live with any CELs that come up until you can get some extensions and move the rear O2 sensors behind the high flow cats and hopefully any codes will extinguish themselves.
Also, did you do the install yourself? If so, any trouble removing the steering rack or the steering wheel moving on you with the rack disconnected?
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From: Markham
07 Z06, 2011 c63pp
Who would want to keep the secondary cat when installing headers? You would beat the purpose of LTH! Either way you do need 02 extensions since your pre-cat sensors are shifted a little bit more downward the path. Therefore your OEM harnesses might be too short. And yes you would need 2 extensions. One for each bank.
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From: Denham Springs,LA
'12 C63 Black Series, '12 ML350 BlueTech
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
Thanks for the feedback! I did purchase the high flow cats, so I'll use the one extension properly on one bank and the other side I'll use the rear O2 bung on the headers, and cap off the bung on the cat until the second extension comes in. I did get the V5 tune, with and without O2 sensors (on/off for the rears), so I'll use "off" for now. Thanks!
Also, did you do the install yourself? If so, any trouble removing the steering rack or the steering wheel moving on you with the rack disconnected?
Also, did you do the install yourself? If so, any trouble removing the steering rack or the steering wheel moving on you with the rack disconnected?
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From: Burke, VA
2014 C63 AMG 507
I did do the install myself. I just removed the steering column connection and heat shields at the rack and the rack stays in place. I was just careful not to move the steering wheel or wheels so everything just stayed lined up. Its been a while but I think there is a piece attached to the joint to help line the spines back up or mark it if you are nervous. I also unbolted the heat shields on the engine mounts to get the headers up into place. There is enough room to get them bolted back in place after the headers are installed.
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06 E55 / 13 C63
I'm curious about the raspy sound and what should be left alone vs modded to keep the deep V8 sound, but increase the dB substantially.
I wouldn't say I'm necessarily against having a bit of rasp (as they increases the sound level) but would want a more clean sound.
Tal- since you've done so many combos with this platform, you would probably be more educated to answer this well.
Can people chime in on the differences in sound, not just loudness, but clean/raspy addition on the following setups (by LTH, primaries deleted):
- resonator deleted only, everything else stock?
- secondaries deleted only, everything else stock?
- LTH only, everything else stock? (
- LTH + resonator delete, stock secondaries and stock mufflers?
- LTH + secondaries deleted, stock res and stock mufflers?
- LTH + resonator delete, secondaries deleted, stock mufflers?
Thanks in advance..
I wouldn't say I'm necessarily against having a bit of rasp (as they increases the sound level) but would want a more clean sound.
Tal- since you've done so many combos with this platform, you would probably be more educated to answer this well.
Can people chime in on the differences in sound, not just loudness, but clean/raspy addition on the following setups (by LTH, primaries deleted):
- resonator deleted only, everything else stock?
- secondaries deleted only, everything else stock?
- LTH only, everything else stock? (
- LTH + resonator delete, stock secondaries and stock mufflers?
- LTH + secondaries deleted, stock res and stock mufflers?
- LTH + resonator delete, secondaries deleted, stock mufflers?
Thanks in advance..
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From: Los Angeles
2012 P31 C63 Coupe Trackrat, 2019 GLE63S Coupe Beast
LTH + secondaries deleted, stock res and stock mufflers
Sounds like stock at idle and below 3k rpm. Sounds crazy at WOT. Still deep. Not at all raspy.
Sounds like stock at idle and below 3k rpm. Sounds crazy at WOT. Still deep. Not at all raspy.
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C63 AMG
Stock mufflers with LTH's are raspy.
Need a solid catback to tone them down. You can keep the stock resonator in place, but still is pretty damn raspy compared to a full setup with a quality cat back system.
Need a solid catback to tone them down. You can keep the stock resonator in place, but still is pretty damn raspy compared to a full setup with a quality cat back system.
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From: eNyCe
Steel Grey Metallic C63!!
Thread Starter
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From: Cincinnati Area
C63 507 with BS Body; 2008 SLK 55
For me the LTHs with stock mufflers were clearly too much (both volume, esp. cold start - and screech/rasp). I added an Akrapovic slip-on and it is a huge improvement. Toned down some, and back to deep rumble. Still louder than stock, but a full tone, more in character for an AMG.
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C63 AMG
The 2 cat backs I had personal experience with are the Akra Slip ons and the Eisenmann Race (which i have on my car right now)
You will change the exhaust note of the car by adding LTH's anyways my friend. The 2 systems I listed are IMHO the finest pieces made for the C63.
Remember Eisenmann makes many OE setups for AMG. Your stock tips on the C63 are made by Eisenmann. So yes it may be a departure from stock,but its still is worth the switch. The car sounds exotic with a nice system. Imagine your LTH setup with an extremely controlled over-run and little top end rasp.
Its hard to describe in words, you have to experience it to truly appreciate what a good cat back can do with LTH's.
You will change the exhaust note of the car by adding LTH's anyways my friend. The 2 systems I listed are IMHO the finest pieces made for the C63.
Remember Eisenmann makes many OE setups for AMG. Your stock tips on the C63 are made by Eisenmann. So yes it may be a departure from stock,but its still is worth the switch. The car sounds exotic with a nice system. Imagine your LTH setup with an extremely controlled over-run and little top end rasp.
Its hard to describe in words, you have to experience it to truly appreciate what a good cat back can do with LTH's.
