I am runing aftermarket header with aftermarket exhaust, but no cat. is this good? also when i installed the new header i noticed that the lower sensor on the manifold could not reach the prongs to where the new location is with the new header. im only running on the one upper sensor. is this bad until i can relocate the sensor prongs? what exactly does the sensor do? i will probably have to tear into the harness to make it long enough to reach.
no cat
- Thread starter yourname9505
- Start date
Running no cat is ok for off road/track use only. Going to get shitty gas mileage, you will throw a check engine light because the sensor is located in the cat. Plus you are polluting the air. I bet your car is loud as hell to which hurts my ears. Put the car together right if this is a street driven car.
So I am assuming what you are saying is you have headers and then just a pipe going to the back, or do you have a resinator(sp)? If you have one, you should be ok, your gas will suffer a little, but not too much, if no rez, youll get pulled over quickly, and it is very illegal to run with out one.
yeah no resinator, and yeah its hella loud. but do you guys actually know what the sensor is for? and im guessing its cool to run without one
the sensor is used to tell the ecm how much oxygen is in the system, which it then adjusts the air to fuel ratio to give you the best milage/polution it can.. also if it doesnt reach just snip the wires and splice em to make em longer, use some waterproof connectors or heat shrink to keep from getting a short. other then that good luck 
Thanks for the info. Also i was wanting to know if its true that you get extra horses if you drop the cat? i think you do because you have no restriction, but it loud as hell!
The HP diffrence is minimal. nothing that youd ever notice
i see. well i need one for inspection and i dont feel like getting a cheap on off ebay and it robb me of power and mess up my exhaust. so do any of you know where i could get a factory cat? i beleive its going to be located right after the 4-2-1 header.
Im running a catco free flow cat, didn't add to much in sound and felt a little more peppy. There are nice bolt on cats ranging around $200 online. Thinking Jackson Racing makes one.
Here you go here are some good cats http://www.modacar.com/products/Honda/Civic/MODAHFC/
what about ebay cats. is it worth the 30 bucks?
Ebay = Junkyourname9505 said:
Getting the Ebay high flow cat is no worse then taking a 3" pipe and welding it in place of the cat. If its not a moving part, or can easily be modified with basic fabrication work, the ebay crap aint too bad, just dont get B series headers off ebay, they dont fit. Really all my exhaust system is, is 3" piping coming out of a cheap on cat (which just looks like a tube when you look through it, I highly doubt it creates any back pressure at all) and some cheap-o resinator that sounds good.DetainedCivic said:
dont you want as less back pressure as possible though?