Hmm, OP I agree with everyone that these cars come from the factory with room to lean out. But that is probably due to the fact that the factory has to design vehicles to run well in every climate. And basically we have extremes on both sides. You have mountains in the Winter that get super cold and then deserts in the Summer that get super hot. So they are tuned with wiggle room. However I don't think you should be seeing black smoke and smudge like that. I mean, if that were normal then every SS would have that around their tail-pipes. I think something is wrong. Are you seeing any CELs? If I were you I'd take it in and have it looked at. My Mustang GT ran rich like a pig with blow thru mufflers and an O/R X-pipe. Yet I never saw that much smudge on my bumper. And I hardly ever washed the thing. A tune will lean it out and give you more performance. But I'd say go have it looked at first. Just to make sure something isn't wrong.
2017 Camaro ZL-1 A10
2013 Jeep Grand Cherokee Hemi 5.7 - Tuned!!
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