Wont hurt at all. Before the days of coatings on headers, they were all just painted flat black but the paint wasn't very good. We used to take 'em out of the box, sandbast 'em and paint them inside and out with a good high temp. header paint. You can even get it in different colors. I used to paint them a color to match the vehicle. It would last about a year and I'd take them off and paint 'em again.
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1985 Mustang GT
'85 GT 13.20 @ 105.8 / '72 Mach1
Long list...check website!!
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