What makes long tube headers (with fittings) not emissions legal?

Is it only because it relocates the cats?

or is there a difference in readings compared to stock when you hook it up to the sniffer?

 

Depends on state law. In most cases it's cat relocation.

 

In all states relocation is illegal, federal law. No difference in readings.

 

Great! Thanks! OK one more question for you, what about Carsound Hi-flow cats? I know they are illegal for OBD-2 cars, is it because they aren't approved, or do they change readings?

 

You're in Thousand Oaks, right? Cali is very strict on smog laws. Unless you know someone who will pass your car, you might have problems going with longtubes. More than likely, when they hear that car fire up, they'll look at it and see the LTs and that you've moved the cats and immidiately fail the car without ever getting the sniffer in the pipes.

It can be done, people have done it, but it helps to know the right people. You find someone to ignore the LTs and relocated cats, then you've probably found someone who will choose not to notice the difference in readings. To the best of my knowledge, however, the Carsound cats work just fine and won't show a dramatic difference with the sniffer.

 

such crap that if the emissions are under the limits, it'll still fail because of a BS technicality. so lame. What's the legality of having a cutout in front of your cats? "no officer, i always have it closed on the street"

 

I'm with you, man. I don't see what difference it makes if it passes the sniffer.

 

Ya i have my guy in the bay area who overlooks the visual test as long as I pass the sniffer =) I'm actually driving up there this Thursday and he's the one installing the long tubes for me. We're gonna smog it at his shop in the mean time.

 

Well, if it passes emissions on a cold start, then there should be no if ans or buts, but the main reason you can't just bring in a car, hook a sniffer up to it and see if it passes is because of all the other things on the car that has to do with emissions. Relocating the cat takes it longer to warm up and causes it to work less efficent, AIR pumps, I think, pump fresh air into your cat to warm it up and make it work more efficiently. All those things in your car heat the cat up to operating temp to make it work better. Basically a cat is more expensive hot then cold.

If the hook it up to a sniffer were to be the way to go, it would have to go through a much tougher test, starting with the car being cold, then testing it, getting it up to operating temp, test it again, and it'd be alot tougher and more expensive way of doing things.

BTW I am no tree hugger, I hate all these emissions things too, and I am yanking them out of my car asap, not because I think it restricts horsepower(it probably doesn't) but these cars have enough clutter already, and I need more room to work.

 

so everyone agree that long tubes and hi-flow cats don't significantly affect the sniffer?

 

haha, i kinda am a tree hugger, if caring about whats going to happen to the planet when my grandkids are around counts. Whats wrong w/ a little clutter? Next you're gonna pull the computer and EFI cuz its got too many wires? That emissions control stuff causes our cars to produce a TINY fraction of what they would without, IMHO they're awesome pieces of technology.

 

(double post, sorry)