maybe putting a cat test pipe the sound gets better?

 

what? a cat and a test pipe are two different things

 

my catalitic converter inside stuff was destroyed by some bad mechanic, they say the ceramic with platinum stuff can be sold for some money. so i put a test pipe on its position, like in the link bellow. the sound and accel gets better and because my civic is a usdm i don't have issues with emission here in brazil, even without cat converter. i'm wondering if worths to put him to ride with ethanol. heard it performs better and pollutes less. and here it costs lot cheaper than gas, even with a weaker mileage the cost benefit seems to worth.
http://cgi.ebay.com/88-91-92-95-96-0...6.c0.m14.l1318

 

a test pipe definitely does not sound better than a catalytic converter.
i understand what you're saying now though
aren't most new cars in brazil running on E85 ethanol?
yea it definitely costs less, here they put like 10% ethanol in our pumps because it costs less... it doesn't seem to be making a difference of the price though..

 

i choose to substitute the hollow cat with a cat test pipe because even an used working cat costs a lot here. yeah, most new cars here can run both in ethanol and in gas, they are called flex. unfortunately my civic is a 97 and if i would run with ethanol must buy a device to allow it, that is what i'm wondering if worth. well, i "inherited" this civic this year and just started to tune it. it seemed to be in nice conditions because was my mothers car, with all revisions in local hondas dealer, gots only 108k km (67500 miles) and so. but already got to fix the torque converter, this catalytic issue and some cv joints. roads here are crap! wish got only fun time from now, tuning it.

 

a hollow cat and a test pipe are the same thing, besides that the hollow cat used to be a working cat. i don't understand why you bought a piece of pipe to replace another piece of pipe that did the same thing?

 

the hollow cat results in some resonance effect that the cat pipe doesn't. the cat pipe inside looks like a high-flow muffler

 

I have the same set up man, except i have a custom mandrel bent set up with and apexi muffler, to trick the computer to think you have a cat, get you two spark plug anti foulers. you can pick them up at oreilly auto parts for like 5 bucks, drill one out so your o2 sensor can fit in it. be sure not to mess up the threads though, and put the two anti foulers together, put your o2 sensor in the top anti fouler, and this puts your o2 sensor farther away from the pipe, thus restricting exhaust flow to the sensor, tricking it into thinking you have a cat. I have been using this in my system for 8 months now with no problems at all, and get a test pipe, that makes the raspiness go away. dont worry about the cat unless the state you live in actually checks emissions when you get your car inspected.