Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: powerslinky on 06 November 2016, 15:28:27

Title: Cats . . 2.5/3.0 onto a 2.6 ?
Post by: powerslinky on 06 November 2016, 15:28:27
Hi guys
            my 2.6 has what seems to be "pattern" cats fitted . . . from a cold start up there is a nasty metallic rattle from the o/s main cat . This noise goes after about 30 seconds. I'm thinking something is loose in there but tightens up on expansion when heating up. it's not really a problem , but sounds pretty awful on initial start up . Once warm . .  no noise  :-\

So question is, will a pair of 2.5 or 3.0 cats , if I can locate any, fit straight on this 2.6 ?

Been a while since I've had a 2.5/3.0 ,but seem to recall they only have one O2 sensor :-\ :-\

Any advice appriciated . . .  TIA     Al :y
Title: Re: Cats . . 2.5/3.0 onto a 2.6 ?
Post by: zirk on 06 November 2016, 15:38:14
Heat shields rattling ?, normally some extra Exhaust clamps or large Jubilee Clips around them sort the job out.
Title: Re: Cats . . 2.5/3.0 onto a 2.6 ?
Post by: powerslinky on 06 November 2016, 16:37:41
Heat shields rattling ?, normally some extra Exhaust clamps or large Jubilee Clips around them sort the job out.

Will have a closer look when I can get it on the ramps.  could be that I suppose  :-\

but it sounds like it is coming from the o/s main cat box section  :-\ :-\

Are the 2.5/3.0 cats an improvement for the 2.6/3.2 engines compared to the std fitted ones ?
Title: Re: Cats . . 2.5/3.0 onto a 2.6 ?
Post by: Migv6 le Frog Fan on 06 November 2016, 17:13:41
I haven't don't it, but I believe the flange needs a little fettling to allow it to fit the manifold properly, and you need to cut a hole (in the right place) and weld in a boss to fit the second lamda sensor to.
Title: Re: Cats . . 2.5/3.0 onto a 2.6 ?
Post by: zirk on 06 November 2016, 17:18:38
Yea I meant the heat shields on the Cats.

2.5,3.0 cats seem to be better build quality, some fit them as a way to get rid of the common O2 error codes that pop up on the 3.2, means messing with your sensors though.

If it aint broke, dont fix it, springs to mind.  ;)
Title: Re: Cats . . 2.5/3.0 onto a 2.6 ?
Post by: biggriffin on 07 November 2016, 06:49:52
Got 3.0L cats on my 3.2. 
There is a how to.
Basically it grind 5mm off the sleeve, and weld a new lanmda boss in after,the cat.
Stops the 420/430 pre-cat code, improves accleration, allows engine to breath better.
Hardest job is finding a pair of 2.5/3.0L cats.