P38A so i changed my cats todaytoday

Long story short I finnally got around to changing my cats I replaced the rest of the system a while back but didn't do the cats at the same time due to time constraints. I had the cats sitting here since Xmas.
I went to fit them the other week only to discover iv got 18mm o2 sensors and the cats had 12mm holes for the cats, seems its a common problem euro car parts list 3 types for my car and 2 of them have 12mm holes to.
So quick search on the bay I found some new 18mm o2 sensor collets I ground the 12mm outs welded in the 18mm job done.


I wrapped it in heat wrap iv a lot of heat wrap so wanted to use it up I wrapped the manifolds when I did my hg instead of refitting the heat shields.

The new next to the old apart from the much smaller cats compared to the old oh and the weight new ones much lighter.
Hardest job was undoing the gear box cross member the 8 bolts securing it were rusted solid took me ages to get them out still job done all works well I refitted my standard centre box to so nice and quiet to.

Top job, any difference in running...were your old cats blocked?

Yes mate big difference in running iv had it out for an hour reset the trip and got 22.4 mpg with mixed driving iv never seen that ever on this motor it did drop tho on the last few miles because I booted it . Iv had a feeling for a while they may have been blocked slight rattle on start up only just noticable , no one else could here it but I could that's gone now mpg is up, whenever I had my centre delete pipe on mpg was up fit the standard centre box it would drop and it defiantly is much much smoother running. I'm happy.

No idea tho what make these cats are no makers name on it I think klarius because it came with the centre and rear boxes complete from the bay the system had been fitted for a week before the motor was scrapped, lucky me lucky bay find Xmas eve lol.