Here's the best part NO EMISSIONS REGULATIONS!!!!!
.We can do just about anything we want with our cars here and not get busted for it. The only way you can is if you et pulled over and the cop is being a dick but its only a $40 some fix-it ticket. Generally just pay it and keep it the way it is. Many cars are straight piped w/ no CAT so that S13 is probably totally unrestricted.
Oh and it didn't get broken up until about 1:00am so it was a good 3 hours