Need Help Urgently Please

**jammin31** · 19th June 2011, 11:22

Im trying to do a de-cat mod and im stuck, my car is in bits at the moment and i could do with some advice.

I read on here that once the front part of the exhaust is dropped there will be a mesh inside that needs knocking out but when i took it off to look its totally hollow but at the end it fits too on the engine side actually has the mesh ??

Can i just knock this all out with a hammer and chisel as best as possible then simply fit the exhaust back on ?

Sounds to easy to me.

I have attached pictures to try and explain easier what im having difficulty in writing lol.

Top pic is the exhaust leading down to what i think is the cat.

The middle pic is the mesh at the engine side ( the side i need to smash up i believe ?? )

Bottom pic is them both seperated

**jammin31** · 19th June 2011, 11:23

vauxhall vectra 1.9cdti 120bhp 07 plate

**merikiito** · 19th June 2011, 11:38

The part with the mesh in is the Pre Cat. Ideally you need to remove this to knock the mesh out unless anyone knows it can be done while still on the car. I would be worried that the turbo would get damaged if you did it while still on the car

**jammin31** · 19th June 2011, 11:40

is this definitley the right piece to knock out though ?

I cant see how you would ever be able to remove it to get to it ?

Anyone know how its removed or can i just tap it with a hammer and chisel all the way around to try and get it out ?

**jammin31** · 19th June 2011, 11:44

sorry didnt make it clear that im actually trying to remove the pre-cat not actually de-cat the car in full.

**merikiito** · 19th June 2011, 12:36

Well you need to take the rad pack out and the heat shield then you will see the spring clip and bolt holding the top part of the precat. On refitting you would need new gaskets from Vauxhall to ensure you have no leaks. You might be able to remove the heat shield without taking the rad pack out but not sure

**jammin31** · 19th June 2011, 12:39

Can it not be done whilst its fitted to car ? im not sure if vibrations will damage the turbo ?

**Jezzy** · 19th June 2011, 12:41

You seem really desperate to dirty the environment even more than necessary...why?

**jammin31** · 19th June 2011, 12:46

Im trying to create more airflow and this restricts it a fair bit, the cat is still in place so nothing is made worse as far as i know

**merikiito** · 19th June 2011, 12:50

Originally Posted by jammin31

Im trying to create more airflow and this restricts it a fair bit, the cat is still in place so nothing is made worse as far as i know

The mesh you can see is the cat! The mesh is what removes or helps remove the particles in the exhaust gas.

I took the pre-cat out altogether and replaced it with a scorpion pre-cat pipe