Yet another headers thread. These are mine finally ready to drive. I decided if I was going to go down this route I might as well go long tubes instead of mid length. Made by an awesome local fabricator on the forum here so being RHD wasn't an issue. The installation took 8 hours + 1 hour tonight to re-tighten and check all of the nuts. Some of the head shields had to be lightly massaged but everything came together nicely. We dropped the small brace behind the cats about 5mm. There is no contact on anything that I can tell while driving. I would strongly recommend doing this install on a lift. You could do it on jack stands but it would be a very long and unpleasant experience. I bought new nuts and gaskets. I would also recommend new studs, every single one came out and the time spent taking the nuts off and trying to tighten new nuts onto old studs is not worth it.
It sounds fantastic. Cold start is louder but then there is almost no increase in noise at idle or very light cruising, absolutely no drone at light throttle. It is a bit louder than I was expecting while accelerating. I still have the stock resonator and mufflers. Hopefully a small bit of head wrap will keep the alternator happy. I got a CEL for the cats (oxygen sensor location) after 100km. I put on the "eurocharged secondary oxygen sensor delete tune" so I will see how that goes. Also hopefully is that the tune is pretty good. I have an innovate wideband kit ready to go on and a small square gauge on order from dyno tune nitrous https://www.dynotunenitrous.com/stor...?idproduct=171 I like the subtle look. Cats are 100 cell from summit racing. It was very hard to find anything at all here.
I am going to get a decent drive in tomorrow and will update is there is anything worth adding. I haven't stomped on it yet.
The primary O2's are reading off two cylinders on each side because the wires won't allow you to get too much further back. The second set of ports is really for wideband placement. The secondary O2's are really just place holders since the ECU didn't like the new arrangement (as expected). I know you can get errors when lengthening the harnesses or using plug in extensions to get behind the cats so I didn't want to go down that route.
Quote:
Originally Posted by PieRat
Haha nice I'm looking at getting these in mild steel next year! I don't have any good photos but the merging looks perfect inside.
whats the story with the o2 sensor config?
For anyone who is interested I used the black series, from FCP euro: Mercedes Black Series Engine Mount Upgrade Kit - Genuine Mercedes 2402400817 https://www.fcpeuro.com/products/mer...17#description
They look externally identical to the ones that came out at a glance. The original ones had 50,000km on them but still managed to crack along the top, most likely from age than anything else. I went for a good drive today. The car is definitely very fast. I felt like the low end torque may be reduced a small amount. The traction seemed a lot better and I know the headers will lower the boost. I think I need to do some timed pulls. Sounds fantastic when you step on it. Still no issues with vibration and no banging around corners etc.
Nice fitment with the head shield looked snug on your last photo but perhaps that was before you massaged it out of the way.
Glad you finally got the exhaust upgrade trust me soon you'll be thinking its quiet again haha!
So true, “...soon you’ll be thinking it’s quiet again...”. PietRat speaks wisdom. 9 months after LTH, x pipe, res delete & no cat I had to pulled the trigger on C63 mufflers.
Haha I don't know about the noise issue, we will see I guess. There is quite a bit of clearance around the headers, it is hard to appreciate with the photos but nothing seems to touch. And of course the reason why we upgrade.... barely a 4cm outlet!
After a bit more driving I can really feel the increase in top end torque/power. At the same time I have definitely lost some low end torque, it doesn't have the same punch at less than 2000rpm. The plus side is that the car is a lot better to drive. I can actually launch it now. I get a tiny bit of wheel spin around 2500rpm (no ecu induced throttle body shut down) and then dead hook. Even in the wet it is a lot more driveable. Of course I have an updated eurocharged tune so I can't say if that had anything to do with this change. I could easily put on a smaller pulley to get some of that low rpm torque back but considering I couldn't stop the wheels spinning before it doesn't seem like a good idea. My wideband gauge should arrive soon and I can get a feel for the AFR's and check everything is ok.
This is a bit more unique situation as almost everyone has 4-1 headers but has anyone else noticed changes in the torque curve like this?
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