Has anyone removed the cat, and modified the exhaust to gain hp, what are your results.

 

I emptied mine from inside, few gains more high end and there is a rattle in the sound because of the empty CAT.

 

Could always purchase a high flow cat or just have test pipe installed

 

Yes you can

 

I did that with my EG w/ ITR w/ ITBs Street Class Car

 

That is unless they integrate the cat into the exhaust manifold like on new civics.

 

what about the heated oxygen sensor for the cat? how would this be tricked out for the ecu?

 

you can just have a bung welded in and then you can add it into the test pipe

 

The removal of emissions control devices such as the cat and EGR earns a A$10,000 fine in Australia. I'm sure the US EPA would take a similar stance. The high flow cats have 2 holes through them instead of 1.

 

Maybe in California. In Texas all they do is the visual inspection. No sniffer test.

 

No testing in Central Illinois but there is in Chicago

 

In Cali I think no cat was like around $1000. That's what I heard. Just don't go to a smog insp with out it. I cruise my stang without cats. Its 15HP easy removing those bad boys. Totally wakes the car up. I put a high flow cat on my '95 Civic when I failed smog because of a crusty old cat. It was stock size though. Not too much difference. The muffler made more difference, but I almost think the extra noise made me think it had noticable power gains. Never dyno'd before/after, so just a guess.

 

dude in certain parts of texas they wont even bother looking at your car. the place that i take my cars to get inspected at just does a quick look around, checks for CEL, and sends you on your merry way. even if i throw a code all i have to do is offer to buy the guy thats always there a sixer and he passes me.