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WydRyd WydRyd is offline
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Join Date: Mar 2002
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Hiya Spence! I believe OEM exhaust nuts are steel with either a copper or zinc coating to resist corrosion/rust and seizure. It's probably zinc as most manufacturers use zinc coatings on their exhaust nuts. BMW use all copper nuts on their M series cars I believe. Zinc or copper coated is best. They never seize up

Use some Anti-Seize on the threads too.

P.S: I'm not sure on using stainless steel on the OEM studs though. Also, s/steel has the undesirable effect of fusing itself to aluminium alloys under extreme temps. I don't think our exhaust studs are of an aluminium alloy... probably just some grade of steel.
'89 911 Turbo Cab
Protomotive MAP ECU, Twin Plugged Heads, GT2-EVO CAMs, 3.3L fully finned P&C's, ARP fasteners, C2T head gaskets, Titanium Retainers, Turbo spec valves, springs & guides, 964 splash valves, GT35R BB turbo, GSF Stainless Headers, Magnaflow Exhaust, Full bay Intercooler, TiAL 46mm w/gate, TiAL 50mm BOV, Apexi AVC-R EBC, SPEC Stage3+ Clutch kit, Crane CDI Ignition

Last edited by WydRyd; 01-03-2008 at 07:50 PM..
Old 01-03-2008, 07:33 PM
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