Another emissions and gas milage question

[W1N]

Hey,

How much performance headers or/and exhaust systems (like the one H2S online store offers) cause more emissions than a stock H2? Or do they? I'm not a tree hugger, but we have some really strict emission laws over here.

How is the gas milage compared to the stock?

Thanks!

[W1N]

Hey,

How much performance headers or/and exhaust systems (like the one H2S online store offers) cause more emissions than a stock H2? Or do they? I'm not a tree hugger, but we have some really strict emission laws over here.

How is the gas milage compared to the stock?

Thanks!