Rockwell28

High flow cats even though they may not meet the tight emission standards they just in a way make you street legal because you actually have cats vs the o/r setup. There will be a slight exhaust restriction with them but not nearly as much as the factory cats. Im guessing thats why they dont meet the factory standard.

terminatorcobra

cats dont restrict at all you prolly wont gain an horsepower itll just be louder a little different tone and it will smell like exhaust. and ur gas milage may go down slightly...a cat help burn un burnt gases and re uses them and tuns them into less harmfull things u dont have them there to reburn and stuff now...if u want it louder then go ahead...

abranger82

And if you dont have CATS and want to make your CEI go out, just order some MIL eliminators. I put them on mine and bing..no CEI light.

cliffyk

Or make them for $5 (a pair)...

kast1376

Depends where you live, and how much knowledge the cop has. I got pulled over, and ticketed for no cats, as the cop saw the pre-cats were not there (as they are missing on my Bassani catted X)

Took it to the local cop shop, showed the cops the cats, and he signed off. I got off on a paperwork mistake.

Rockwell28

oh ok gotcha.

98redstang

I passed emissions here with lts and high flow cats.

Rockwell28

Yeah I have passed here 2 years str8 with high flow cats. But it was a vehicle inspection not emissions though.