De-cat question.

[Corin Denton]

I am almost certain I am going to remove the two primary cats from my 400 Chimaera , what do I actually have to do ? Is it as simple as removing the manifolds and tapping out the ceramic monoliths? What are the emission readings like afterwards , does it still pass the BET test for M.O.T.
Sorry , another noise junkie !

[mongoose]

spoke to mark adams about this one-discussed recently on a thread here.mark said that if you remove precats then emmisions will still be fine,no need to alter ecu,lambda sensors etc,just remove them.however they dont come out without a fight,mark told me you can get through a couple of cold chisels trying to knock them out which put me off!apparently some company/companies will remove them for you by cutting and re-welding the pipe,but sorry i dont know who or how much they charge.another benefit is that on removing them you get smoother bottom end revs.its worth adding that my car is a griff 500hc by the way,so this may make a difference?would you let me know how you get on please?

[JamieBeeston]

I can confirm that my 450 passed its MOT with flying colours, after a Tim Lamont (ACT) De-PreCat install, followed by a Mark Adams retune.

Well under the limits on the machine, with them virtually tapering off to zero at 3000 rpm (too high on the revs for them tho :P)