removing catalytic- will it be loud?

[e36325is]

hey guys/gals

So i went to the mechanic yesterday for an oil change, my car was up on the lift, when i was under it looking at it, my mechanic pointer out the catalytic converter and its pipes, they are not even BMW!!!!!!!!!! the cat and the pipes are so small, they guy who put them in had to insert the small pipe into the larger ones up against the side, then he welded the 1 1/4 inch gap!! what a nad.

So i have decided, since i do not have to get emissions for another 1 year and 5 months, i am going to get rid of my cat all together (for now) so i will have the correct size pipes from the headers all the way back to my muffler, could i expect louder noise? decreased performance (since no cat) or improved performance? (since no cat restriction)

thanks for any input

-Love
Ben


(jk)

 

[Steve Neu]

Get it fixed right the first time. Clean running cars are good for everyone.

Steve

 

[frolf]

true that, id on't want to smell your car at a stop light, but you should notice a little bit more power.

 

[wood_e]

get the right stuff put on there... if its bigger it will flow a bit more, and having a good cat on there will increase your low end a bit, but removing the cat increases high end...

I say put a cat on and get it done right.

 

[frolf]

oh and it will throw your car into a loop, o2 sensors gone wild

 

[Kirby]

I did this years back on a 77 Mustang. Converter was shot, no emissions tests, and it was not illegal at that time (I think) to remove it after it was dead. Anyhow, you could buy pipes that bolted in place of the converter. It made no difference, sound or performance wise.

I agree with Frolf, the ECU will probably get nuts reading the O2 sensors. It might actually perform worse if it tries to compensate the air/fuel ratio. And it might keep throwing a diagnostic error code.

 

[Looky]

ohh yeah it's getting louder AND slower !!!!
you'll get a drop in pressure off your exhaust system. The result is a very bad mixing off the gases in your cylinders. We testet it last year in a M50B25 of my friend. The sound was cool but we had less torque and power...

Your thought is quiete good to reduce the pressure, it truly works but only in a small range ... cause the hole exhaust is a komplex system. There're many parameter which are dependent on each other.

Some cars run better without catalytic converter... for example --> VW Vr6 2,8/2,9L

Buy some race catalytic converter like from http://www.hjs.com/hjs_englisch/index.htm
and you won't get any troubles with the blue-white race patrol

cya
Looky