My car (MY94 WRX) is fitted with a down pipe cat as standard, the mid section just appears to have a resonator box. I have replaced my downpipe with a catless one and I was wondering if I would pass my MOT if I put a mid-section cat on it (just for the test ;D ) as this would be a lot less work.

Will it pass with the mid-section cat only? If so can I get one cheap from somewhere.

I could just put the downpipe cat back on for the test but I am also moving the Lambda sensor to the downpipe and this will make it harder to swap around.

 

If you get the cat hot enough in the ctrpipe it will pass......