Calling All ARH Long Tube Header Owners!
- Should I re-use factory header bolts or get ARP?
- If ARP, do you have a part #?
- Should I use factory gaskets or aftermarket?
- Header Wrap: Yes or No? If yes, how many feet?
- Are the O2 sensors plug-n-play or do I need longer wires?
- Should I use anti-seize compound on the bolts?
- Do I re-use the factory bolts for connecting to the resonator?
Anything else I should consider to make for a smooth install?
Thanks!
- Should I re-use factory header bolts or get ARP?
- If ARP, do you have a part #?
- Should I use factory gaskets or aftermarket?
- Header Wrap: Yes or No? If yes, how many feet?
- Are the O2 sensors plug-n-play or do I need longer wires?
- Should I use anti-seize compound on the bolts?
- Do I re-use the factory bolts for connecting to the resonator?
Anything else I should consider to make for a smooth install?
Thanks!
New OEM manifold gaskets and copper nuts
New OEM resonator gaskets (you can reuse the nuts and bolts to reconnect)
Wurth exhaust puddy (My MBH kit is slip fit)
I did not use anti-seize
Disconnect the battery before you begin working on the passenger side
ARH is good about providing O2 extenders if needed for the installation. I am not sure if you will need them or not.
I'll get some new copper nuts and gaskets and stay away from the header wrap. Now I just need to sell my Subaru so I can pay for these bad boys!
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I installed ARH headers last winter. I had mine ceramiccoated. They were easier to install than the Kleemann header I replaced. I wasable to re route my O2 sockets & did not need extenders. The headers tocome with some thick heavy duty gaskets & bolt to the factory exhaust. Thewrong size bolts (M7) are supplied with the kit. I called ARH & was toldthat according to their records all AMG heads use size M7 bolt/studs. I orderedM6 bolts from McMaster-car http://www.mcmaster.com/#92820a335/=yhe683. If you reuse your studs I would install them after the headers are in place, Iam not sure there will be enough room to swing the headers over installed studs.I have more photos of the install & can post if interested.
I installed ARH headers last winter. I had mine ceramiccoated. They were easier to install than the Kleemann header I replaced. I wasable to re route my O2 sockets & did not need extenders. The headers tocome with some thick heavy duty gaskets & bolt to the factory exhaust. Thewrong size bolts (M7) are supplied with the kit. I called ARH & was toldthat according to their records all AMG heads use size M7 bolt/studs. I orderedM6 bolts from McMaster-car http://www.mcmaster.com/#92820a335/=yhe683. If you reuse your studs I would install them after the headers are in place, Iam not sure there will be enough room to swing the headers over installed studs.I have more photos of the install & can post if interested.
I did not take photos during install. with a hoist, installation not very hard. Here are the photos I have. If you need a particular photo let me know & will make one. Also perfect time to consider new motor mounts.
Bad motor mounts are what allowed me to "justify" a new set of headers. I have two bad mounts and two cracked manifolds because of it. Since I'm doing the work myself, the total cost with new headers is about the same as having the dealer install new mounts and new OEM manifolds.
Thanks for the pics!
I installed ARH headers last winter. I had mine ceramiccoated. They were easier to install than the Kleemann header I replaced. I wasable to re route my O2 sockets & did not need extenders. The headers tocome with some thick heavy duty gaskets & bolt to the factory exhaust. Thewrong size bolts (M7) are supplied with the kit. I called ARH & was toldthat according to their records all AMG heads use size M7 bolt/studs. I orderedM6 bolts from McMaster-car http://www.mcmaster.com/#92820a335/=yhe683. If you reuse your studs I would install them after the headers are in place, Iam not sure there will be enough room to swing the headers over installed studs.I have more photos of the install & can post if interested.
How did you get the rear O2 wires to reach all the way to the plug? It looks like the white plugs at the top of the picture are in their factory clips, but the black plugs for the primary O2 sensors had to be moved. Did you use the supplied extenders for anything? It looks like they sent me two oil level sensor extenders. I'm not sure how to proceed.
How did you get the rear O2 wires to reach all the way to the plug? It looks like the white plugs at the top of the picture are in their factory clips, but the black plugs for the primary O2 sensors had to be moved. Did you use the supplied extenders for anything? It looks like they sent me two oil level sensor extenders. I'm not sure how to proceed.
Will the car run OK if the secondary O2 sensors are screwed into the pipes but NOT connected to the wiring harness? I know it will throw a CEL, but can I drive it and will it run normally anyway? Or do I need to wait 'till I can plug the holes in the pipe and connect the O2 sensors to the wiring harness and tie them up out of the way?
I thought I'd post some lessons-learned for future buyers. First, here are the answers to my original questions:
- Should I re-use factory header bolts or get ARP?
- Re-use the factory studs with new OEM copper nuts - If ARP, do you have a part #?
- N/A - Should I use factory gaskets or aftermarket?
- Use new OEM steel gaskets - Header Wrap: Yes or No? If yes, how many feet?
- The consensus seems to be an emphatic NO! - Are the O2 sensors plug-n-play or do I need longer wires?
-
The pre-cat O2 sensors will work, but you need to slightly re-route the wiring harness, taking the plugs out of the clips. The headers DO NOT COME WITH EXTENDERS for the rear O2 sensors. You will need to plug the holes in the post-cat O2 bungs. Then, keep the O2 sensors plugged-in to the wiring harness, but zip-tied up out of the way. This will throw a CEL, so you'll need to have someone with STAR code them out. (The car runs fine though) - Should I use anti-seize compound on the bolts?
- No, but I did use blue locktite on everything - Do I re-use the factory bolts for connecting to the resonator?
- Yes, factory bolts were fine, but got new gaskets (two different part numbers) going into the resonator
Overall the process went pretty well until I ran into fitment issues. The old system came out quite easily. Working on a stainless steel exhaust is WAAAAY better than those rusty old steel ones from the muscle car era! The headers slid into place easily, even though the car was just on ramps, not a lift. Only two of the nuts were really hard to reach and they tightened OK with just a little patience. The motor mounts were a breeze with the exhaust out of the way, so definitely do those at the same time.
I also added a PLM H/X at the same time as the headers, and after a weekend of racing I can tell you that those two mods on an otherwise stock car will shave about 0.15 seconds off your 1/4 mile ET.









