That bluing is totally normal. And pretty.
No. Unless the TPs are improperly mounted, they are not hitting the frame or engine. The scratches and dents are most likely from misc road debris bouncing up and hitting them. Unless you only drive on roads that are perfectly smooth with no loose pebbles or anything on the road surface.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |