I like the powdercoating idea
Gunmetal
I have the discoloration also.
Interesting thing is that when I removed and replaced the gasket when I installed S1, the gasket was clean and dry.
That manifold should have only air running through it.
UNless the cast aluminum is porous enough to allow oil vapor to settle in the only area that has turbulence along the track.
Kinda like with endocarditis: bacteria settle around a valve leaflet because of turbulence that allows it to settle. Especially when it is generated by an abnormal valve (MVP, bicuspid aortic valve, floppy chorda tendinae). maybe it's the same thing with oil vapors along the gasket seal and have diffusion of oil along the interface between the gasket and manifold and then settles along the base of the runners.
Or, everything I said is complete bullsh-t[
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2003 GT Inferno Red,5-spd,Eibach Springs,Koni Sport Adjustables, Eibach front and rear Sway Bars, Mopar Stage 1,Mopar BOV,Custom 2.5\" Dual Tip Exhaust (Magnaflow),Hurst Short Throw Shifter, Pioneer DEH6500 Headunit, RF Punch 300 and 301 Amps,RF 12\" Sub and MB Quart Reference and Premium Speakers,Ronal RT 17x7.5\'s with Michelin Pilot Sport 225/45ZR17s, Koni Adjustible shocks, Keystone single scoop, GT Airraid Intake, Mopar Ground Effects
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