I am wanting to reinstall my decat downpipe.

Currently run a full RCMS system with their 'catted' downpipe and it has been mapped with this on it. However I do notice that it does not have the response of the decat pipe.

Will it need a remap? Worst case I suppose I install and if I pick up any knocking I can swap back.

 

yes mate it will require remapping if you fit a decat downpipe, plus you will get the full benefit power gain wise.

i think im right in saying you will need the RCM decatted downpipe as i dont think the systems there systems are interchangable