first do performance even help that much (meaning non race headers)? and second which performance headers brands are street legal?

 

The regular "header" since we only have one.... is basically a waste of time if you are modifying for performance. But if you are worried about carb and emissions a RH is out since it eliminates the catalytic converter unless you cut out part of your exhaust and stick a high flow cat in there and relocate your secondary oxygen sensor.

I believe most all the standard header brands are legal because they leave the OE Catalytic converter and really don't do anything for you. If you get K-pro I would just buy a full race header. You can still pass emissions (I did)