Catalytic Converter, what does it do?

[MadsHilde]

Hey guys

I saw this product at fordprobestore.co.uk, but what does it do? Is it just for better sound? Are there any downsides to installing it, other than that the car will pollute more?

http://www.fordprobestore.co.uk/store/p ... ts_id=3544

[muttpower]

Yeah, that's just a stock cat convertor...where to begin...ok, basically, a catalytic convertor converts unburnt hydrocarbons.....you know what, click this link and read...http://auto.howstuffworks.com/catalytic-converter.htm

[wytbishop]

Catalytic converter reduces polution by removing unburnt hydrocarbons from the exhaust gas. The downside is that it adds a point of restriction to the exhaust system which is something that most "tuners" don't like and try to avoid.

I always figured if I was going to drive a 20 year old car that gets average fuel mileage at best the least I can do out of respect for the planet is to clean up the exhaust gas a little.

[MadsHilde]

Oh, I must have misunderstood then. I thought it was a device to get rid of the catalytic and gain a couple of more HP. If I take off the catalytic (is that what it is called?) and replace it by just a straight pipe, would I gain anything or would the sound be better?

It is quite hard to explain car stuff in English when it is not ones native language, I hope you understand.

[Ryan]

Catalytic isn't a thing, its an adjective.

it uses a catalyst to convert bad gasses to less-bad gasses.

its an emissions/environmental thing.

If you remove it, you won't pass emissions, it will smell different, it will sound a lot different, and it should be a little faster.

[MadsHilde]

Well, I really would like some more sound and a few more HP's, but at the expense of the planet, maybe not.

And thanks for explaining the difference between catalyst and catalytic. So many new words I have to learn when it comes to cars.

[Inodoro Pereyra]

Hey Madshilde, welcome to the forum.
What's your native language? If it's Spanish, maybe I can help.

As Ryan accurately said, a catalytic converter operates by a process called "passive catalytic conversion". In this case, it uses a catalyst (platinum) that, when heated up by the exhaust gases, breaks down the complex molecules into simpler ones (CO and CO2 into C and O2, NOx into N and O2). It doesn't do a perfect job, but it's better than nothing.

Replacing the catalytic converter for a straight pipe will definitely give you a throatier sound, and will give you more power...for about 2 minutes. Then, once the oxygen sensors heat up, and the ECU starts reading them (the ECU ignores the oxygen sensors for about 2 minutes when you start the car, to give them a chance to get to their operating temperature), you will get a CEL, as the signal from the downstream oxygen sensor will be off specs (because the exhaust is much dirtier than it should be), and the ECU will detune the engine to try to get the signal right.

In short, don't do it. This forum is chock full of information on how to increase power in your car. Take your time, read, and ask questions. We're all here to help.

[wytbishop]

MX-3 O2 sensors are both before the cat. Just so's you know. The ECU does not sense O2 before and after the cat like most other cars. Just front and rear bank.

[MadsHilde]

Thank you very much, Inodoro Pereyra. Very informative post. I'm actually from Denmark and this is my first time on an English Mx3 forum, so I've got quite a few new words I have to learn, but I'll take that as a challenge.

I guess, all would like more power in their cars, including me, but I am not very keen on offering too much money on my car and I guess there is no cheap way to get extra HPs.
So far I have done kinda nothing other than new rims, CAI, SuperSprint muffler and lowered the car a bit. It's way too expensive to really add any HPs here in Denmark.
A rule of thump is that it costs around 115GBP pr. HP and 5 extra HP's doesn't do any real difference on the car but it does to my bank account.

I will try to read a lot of posts from this seemingly great forum so that I can get more knowledge on my car. My car is kinda hobby that comes and goes and right now I love my car;0)

[Inodoro Pereyra]

Glad I could help. Sorry you're on your own with the language thing...

Horsepower is expensive pretty much everywhere. If you're willing to learn, and work on your car, you can offset some of that cost, but in the end you will have to spend some.

Being that you live in Europe, I'm pretty sure taking the cat off is not an option for you at all, as environmental laws are really serious there (as they should be everywhere). Living in a state that has no emissions testing, there are no words to ell you how much I envy you...

Anyway, stick around. You won't believe how easy it all becomes, once you start to learn the basics.