soozookabluS2k

i think aftermarket headers usually have thinner wallls so u hear like a hissing sound

Zeeb

wtf u talkin about?

S2K Sideways

is that true? or is that a myth lol

neveronlines2k

After installing my Mugen header the car sounded different. kind of what you are describing, but not really a hissing sound just more airy (sp) if that makes any sense. I think it does have to do with the thinner walls of the header + no heat shields covering the most of header and bouncing soundwaves around (like the OE header would).

Its completely normal and nothing to worry about. If there are no leaks then you are fine