I'm sure that this is coveres elsewhere on the forum so for asking this question again, my apologies.

Can you make a street ported engine road legal? what kinds of emissions are we talking about here. I have a s5 tII engine sitting in my garage, a dremmel too, its all very tempting...I just wna to know exactly what I'm getting into. Everyone seems to have a different take on porting these days. I'm not looking for outrageous gains here either (although they would be nice ) the mods I'm working with are a custom 3to 2.5 in exhaust, intake, clutch, ecu, etc. I'm guessing without a street port it will be round 220 hp or so.

Please any advice would be super appreciated. godspeed ladies and gentlemen

 

Yes, Keep in mind the more overlap and longer port duration the greater the unburnt HC emmisions especially at idle and low rpm, and the higher the idle required.

I have even seen a bridge pass emissions, although the bridges where pretty small, and 2 of the largest/longest available HF cats where required with the airpump connected directly split between the 2. The lowest steady idle achievable was right on the max that they would allow for the test, like 1200 iirc.