Aftermarket Plenum Not Epa Friendly..

[ARTZ]

how could it affect emissions..?

[Downforce]

More air coming in to the engine, changes the air/fuel ratio, which in turn affects the exhaust emissions that come out the other end...

[ARTZ]

it can only get in what your throttle body lets in though cant it..as long as you havent uped the boost it shouldnt change..

[Sunkist]

if your stock plenum only allows for so much air, compared to a new one. then it will change.

regardless of the throttle body size, if the stock plenum doesnt max out the TB, and the new one can then is an AFR difference

[W0rp3D]

These ebay manifolds have a well documented habbit of leaning out a couple of cylinders, that in its self means the afr's have changed.

[Thelen]

Hmm OK must have missed that. So damn confusing all the different states having different laws for everything from cars to fingernail length.

[joeyjoejoejuniorshabadoo]

in victoria it's pretty much illegal to put a sticker on your car, let alone modify something as horrifically bad as a plenum or aftermarket rims

[Count Grantleyish]

in victoria it's pretty much illegal to put a sticker on your car, let alone modify something as horrifically bad as a plenum or aftermarket rims

Yup.

But people do it anyway.