Exhaust Catalytic Converter Requirements

Adsy9

Paid Member
Recently brought a 197 with almost a full years mot on it so I have time to consider.
I knew the car had a gravity system from manifold back but turns out this is a de cat system. It also has a Toyo/gravity manifold which removed the first cat? From the looks of it.
Which of the two is needed to pass emissions? I’m going to look at buying a standard cat to make the gravity system essentially a ‘cat back’
Any help is appreciated thanks!
 
The OEM manifold has a pre-cat in it which was enough to get my car through MOTs on emissions without the main cat.
 
I have an Akropovic exhaust and when it was last tested by my local MOT garage, which usually find things to complain, about they were fine.
 
This is mine with just the main cat,no cat in the manifold,it wasnt even fully warm so I would say the main cat is more than enough to pass,I dont unerstand why they put two of them either.


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Thanks, looking like a main cat is on the cards then to make sure it’s passable at mot time.
Appreciate it!
 
Just had my MOT done today, went to book in and they had a slot open at the time, so had it completed then and there. So car had driven 3 mins and left to idle for a bit.

It passed absolutely fine with a secondary decat and milltek exhaust. They actually did the test twice, once to see what results it would give, those results timed-out whilst actually conducting the MOT, so they had to redo emissions.

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