ARH header install
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ARH header install
Probably a dumb question, but for those of you that have installed headers on your c8, did you (can you?) reuse the OEM header gasket? ARH supplied some thick paper type gasket, but wondering if it's better to reuse the factory metal gasket.
Thanks!
Thanks!
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Drifting
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This is exactly the route I went as well. Took it out for a drive today (first time) and there seems to be a lot more chatter and almost like a hissing noise around 2.5 - 3k under light load. Do you hear the same? Waiting for her to cool off and will check for any obvious leaks (soot around the header and cat flanges) but reading around, a bit more noise and even sometimes a whoosing or hissing can be considered normal with the thinner header walls? No CEL or anything so far but probably only went 20 miles of mixed driving. Thanks to all again for the help
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Thes cars are pretty sensitive to any type of exhaust leak, so I'd think you would get a code.
Racer
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check that the flange on the ARH's is flat. they include the thick gasket to make up for the crappy not flat flange on the headers. I too wanted to reuse the stock gasket as its quit nice with the heat shielding but the headers wouldnt seal appropriately with the stock gasket.
Good luck.
Good luck.
Drifting
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I used the gaskets that came with the ARH with no issues.
Instructor
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check that the flange on the ARH's is flat. they include the thick gasket to make up for the crappy not flat flange on the headers. I too wanted to reuse the stock gasket as its quit nice with the heat shielding but the headers wouldnt seal appropriately with the stock gasket.
Good luck.
Good luck.
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Dang this community is awesome. Between the step by steps posted by @Kracka and some others across different threads, and people chiming in with tips, really appreciate the info guys. Will be checking the tightness on the bolts again today. Still haven't seen any soot around any flanges at this point, but if everything is still tight, I'll probably pull em off and try the thicker paper type gaskets that came with the headers. And check for flatness on the flange. That will actually bug me quite a bit if there's an issue there considering ARH is supposed to be the "best" (debatable from all of the threads I've read I know). Oh well. It's been quite a few years since I did headers myself and I'm sort of kicking myself for forgetting to check the basics before slapping new parts on. Oh well live and learn 
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. I just checked the torque on all of the bolts and they're at spec (18 ft/lbs I believe - tightened from the center out). Still no soot around any flanges. After taking it for a test drive, the only way I know how to describe the noise is it sounds like something rattling around inside the exhaust, and only when I get on it enough. Like metal flakes in a laundry dryer l if that makes sense. I might pop one side off just to take a look inside, blow it out and check the cats substrate as well. Not sure what else to check as there is plenty of clearance virtually all around the headers and cats from the body. Tried to get a recording, but the iPhone doesn't really pick up the noise I'm hearing, sadly. Full disclosure, current mods are:
- Gwatney ported intake manifold
- Halltech intake
- Soler ported TB (95 effective)
- ARH headers 1 7/8
I hear a lot more of the drivetrain (ticking) which doesn't bother me at all, but its the swirling or rattling noise that bugs me. Will keep at it, and thanks
1st Gear
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C8 ARH header flutter sound
Yeah frankly I'm about there . I just checked the torque on all of the bolts and they're at spec (18 ft/lbs I believe - tightened from the center out). Still no soot around any flanges. After taking it for a test drive, the only way I know how to describe the noise is it sounds like something rattling around inside the exhaust, and only when I get on it enough. Like metal flakes in a laundry dryer l if that makes sense. I might pop one side off just to take a look inside, blow it out and check the cats substrate as well. Not sure what else to check as there is plenty of clearance virtually all around the headers and cats from the body. Tried to get a recording, but the iPhone doesn't really pick up the noise I'm hearing, sadly.
Full disclosure, current mods are:
I hear a lot more of the drivetrain (ticking) which doesn't bother me at all, but its the swirling or rattling noise that bugs me. Will keep at it, and thanks
. I just checked the torque on all of the bolts and they're at spec (18 ft/lbs I believe - tightened from the center out). Still no soot around any flanges. After taking it for a test drive, the only way I know how to describe the noise is it sounds like something rattling around inside the exhaust, and only when I get on it enough. Like metal flakes in a laundry dryer l if that makes sense. I might pop one side off just to take a look inside, blow it out and check the cats substrate as well. Not sure what else to check as there is plenty of clearance virtually all around the headers and cats from the body. Tried to get a recording, but the iPhone doesn't really pick up the noise I'm hearing, sadly.Full disclosure, current mods are:
- Gwatney ported intake manifold
- Halltech intake
- Soler ported TB (95 effective)
- ARH headers 1 7/8
I hear a lot more of the drivetrain (ticking) which doesn't bother me at all, but its the swirling or rattling noise that bugs me. Will keep at it, and thanks
Drifting
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Did you ever figure out the cause of your noise? I have a very similar install with ARH headers and OEM gaskets on my C8 HTC. I've triple checked for leaks by pressurizing the exhaust and spraying soapy water to look for bubbles. I'm not finding any leaks but keep doubting myself as the fluttering noise persist.
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Did you ever figure out the cause of your noise? I have a very similar install with ARH headers and OEM gaskets on my C8 HTC. I've triple checked for leaks by pressurizing the exhaust and spraying soapy water to look for bubbles. I'm not finding any leaks but keep doubting myself as the fluttering noise persist.
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Existing mods are in a post above, but at the time, yes only the headers. Unfortunately, I can only go by the "butt dyno" effect for myself at this point, and yes more fun was had at full throttle. But overall, I just like to tinker