Yes it is very illeagal...and yes...switch back for smog

 

is the different smell easily noticable silver9k? i'll be running it on my stock exhaust for awhile until i get an exhaust...i'm juss scared of gettin caught

 

i duno about on stock exhaust, but on my setup, the smell is very noticable.

 

I just put on my Spoon test pipe(straight pipe) on my HKS dual exhaust today. Noticed that it was of course louder. I wouldnt say double but maybe 20-35% louder. I didnt notice a smell at all though. Feels great going through gears and hearing her scream

 

you can notice the smell if you try to. But, if your worried about cops smelling it...don't, just turn your car off before you pull over and coast to a stop if thats the case...

its not a bad smell though, just a little richer in fuel