Legality of a De-cat...

I suppose this should go in the general “Lotus” section, but I’ve started so I’ll finish

I’ve posted this on MLOC, SELOC and EVO but never really got a definative answer, and I know plenty of you have gone the de-cat route

Is a De-cat illegal, in the sense that all post-1993 cars that don’t have them fitted are no longer road legal?

Or is it simply that the majority of cars without them don’t pass the MOT emission test, which makes them illegal on emissions alone?

The Elise I’m due to collect has a de-cat, but I’m not sure if I can actually declare it on the insurance (Tesco - due to the above mentioned) and I’d rather not drive around in a car with undeclared mods.

Can anyone clarify the situation for me? What have you de-catted lot done?

Cheers guys!


As far as I am aware, as soon as a car is exceeding the governments emmisions levels it is illegal, whether it has an MOT or not. I read something a while ago about how Big Brother (AKA: the government) was planning to start random ‘drive by’ emmisions tests as a way of collecting yet more tax, or in their words, cleaning up the environment. If you can get the car through the emmisions test without the cat (very unlikely) then fine, you aren’t breaking any rules.

So what do you Exige guys do?

Obviously you can’t declare an illegal mod, so I assume your all just hoping you aren’t involved in an accident !

I have my CAT on, (sports one).
Never without a CAT.

I have four CATs…

Gizmo, Rambi, Pushy and Panda

I knew somebody had to say it…

I took my car to a garage and asked them to help my engine breath more easily and they fitted a new box where the Cat was that must actually be a Cat