Hi all

 

I have a cat-back resonated scorpion exhaust currently installed on my vrs. I'm looking at possible getting the down pipe and de-cat for my car. Will this effect an MOT? And also will it need a tune to run correct?

 

Many thanks 

If the MOT tester thinks the cat has been removed and (maybe or, not 100% sure) the emissions don't meet the limits for a cat-fitted car then it will fail.

24 minutes ago, hazzaardous said:

Will this effect an MOT? 

 

Highly unlikely to pass an MOT unless the tester is blind and bent. Automatic fail if cat is missing or modified. Specific section in MOT to check for presence and modifications of catalytic convertor as well as emission test which is unlikely to pass without the CAT (on CO and HC)

 

You are obliged to declare all such modifications to your insurer who is highly unlikely to accept a decat as it is illegal plain and simple

 

https://www.gov.uk/government/publications/modifying-your-vehicles-emissions/modifying-your-vehicles-emissions-the-legal-safety-and-health-implications

 

 

What is the distinction between a "fail" and an "automatic fail"?

37 minutes ago, J.R. said:

What is the distinction between a "fail" and an "automatic fail"?

 

https://en.m.wiktionary.org/wiki/automatic#Adjective

 

necessary, inevitable, prescribed by logic, law, etc.

Spitting at another player means an automatic red card.

 

I would consider a sports cat. Not a lot of difference in flow between a good sports cat and a decat.

On 20/09/2020 at 08:59, hazzaardous said:

Hi all

 

I have a cat-back resonated scorpion exhaust currently installed on my vrs. I'm looking at possible getting the down pipe and de-cat for my car. Will this effect an MOT? And also will it need a tune to run correct?

 

Many thanks 

 

If anything with the exhaust filtration system is messed with, it will affect the emissions regardless of whether it's had a remap or not. As said above, if the test thinks any of it has been messed with, it's a fail. It's similar to people who hollow out their DPF's to try and make it appear they're still fitted. They're wise to that one. Whilst it's not illegal to remove such gear, I've seen a few people on other sites who've been fined by VOSA because they're driving on a public road without them fitted and it's been obvious they're driving a car which should have a DPF because of the smoke being emitted.

 

For the sake of a few potential extra horsepower, I wouldn't bother the hassle of attempting to get your car to pass it's MOT and running the risk of having your collar felt with running a decat.

31 minutes ago, tunedude said:

 

If anything with the exhaust filtration system is messed with, it will affect the emissions regardless of whether it's had a remap or not. As said above, if the test thinks any of it has been messed with, it's a fail. It's similar to people who hollow out their DPF's to try and make it appear they're still fitted. They're wise to that one. Whilst it's not illegal to remove such gear, I've seen a few people on other sites who've been fined by VOSA because they're driving on a public road without them fitted and it's been obvious they're driving a car which should have a DPF because of the smoke being emitted.

 

For the sake of a few potential extra horsepower, I wouldn't bother the hassle of attempting to get your car to pass it's MOT and running the risk of having your collar felt with running a decat.

 

Think I may just go ahead with the down pipe on it's own then. Just want to get the car ready for stage 2! As already at stage 1. Many thanks 

1 hour ago, hazzaardous said:

 

Think I may just go ahead with the down pipe on it's own then. Just want to get the car ready for stage 2! As already at stage 1. Many thanks 

 

If you get a sports cat and have it mapped, you should be good to go.

 I carry out MOT's for a living and a missing or played with cat is a fail regardless, same as DPF (we are actually trained to look for any welds or anything that looks out of place. A good quality sports cat is the way to to go as a good re mapper should be able to to do stage 2 with them in place (including the dreaded EGF)