My friend wants to get new ones and he says he'll sell me his chrome MAC equal length headers for 100$ and he'll put them in for me (i have stock headers). Is it worth it? He says its a little discolored but its not too blue.....(as the chrome tends to get from the heat.....plus i heard i can polish the headers back to chrome with some Mothers Polish.....How much HP will i gain? on my farely stock engine? Will it make my exhaust any louder? thanks for your help~!!