Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: stevi1 on 15 September 2009, 22:11:59

Title: decat 3lt mv6
Post by: stevi1 on 15 September 2009, 22:11:59
Was thinking of decat on my mv6 but a lad told me not to as they need back pressure to work properly. Is this true or rubbish? cars for drifting so trying to get as much power as i can.
Title: Re: decat 3lt mv6
Post by: zirk on 16 September 2009, 02:02:47
Quote
Was thinking of decat on my mv6 but a lad told me not to as they need back pressure to work properly. Is this true or rubbish? cars for drifting so trying to get as much power as i can.

Looked into this one myself, as I proposed running the MOT test as LPG only.

Anyway told you get about 12 to 15 bhp gain, the sensors on the cat would have to remain in place or fooled somehow, as there purely airflow rather than Cat sensors if that makes sense on the 2.5 / 3.0.

Although not true on the 3.2 / 2.6 as there supposedly proper Cat sensors?

Chris.  :y
Title: Re: decat 3lt mv6
Post by: Burtle on 16 September 2009, 10:02:00
I've always run mine without the cats, the 1998 3.0L engine I have only has precat LAMBDA sensors so removing the cat's makes no difference to the ECU. I'm not sure if there is a power gain or not, as I've never tryed it with the cats, there not needed in my application.

Cheers
Nath
Title: Re: decat 3lt mv6
Post by: Mr Skrunts on 16 September 2009, 10:13:19
This could be the most stupid question ever, but will post it anyway.  I dont know the science behind how they work so bear with me.

Does the Cat have to be at the front of the exhaust system.

Could one be adapted to be fitted at the end of a stainless system for the MOT and then taken off afterwards and refitted with the stainless end section.

As mentioned it could be the daftest question ever, but if you dont ask you dont learn.  ::)
Title: Re: decat 3lt mv6
Post by: Burtle on 16 September 2009, 10:20:03
In order to work the cat needs hot exhaust gas so has to be as close to the engine as is possible.
Title: Re: decat 3lt mv6
Post by: stevi1 on 18 September 2009, 22:46:37
I removed the cats not sure if it made muck difference. dont like how it sounds now real tinny noise of it. I'll know better tomorrow after i do a bit of drifting if it has anymore power. :y