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Discussion Starter · #1 ·
Right then, just had car mapped and picked up new intercooler, so next is exhaust, already have milltek cat back fitted but want to know what advantages apart from cost a decat will have over a race cat. Also 100 or 200 cell, again pro's and con's of each. I also aware on MOT issues with decat but not realy a problem with that.
 

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Decat is loud and will pop and bang a lot.
It will also fail an MOT, and is probably (although people will debate this to the death) illegal.

Sports cats are more expensive, can be just as good performance wise, but are much more expensive.
 

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If your not fussed about having to swap out the Decat for MOT's then you may as well go for a decat.

The 100cel cat is the least restrictive you can get whilst staying legal.

You will need a Lambda spacer with a decat to avoid the emissions warning light coming on but you may need it with a sports cat too.

You will also need to check your insurance company will insure you with a decat as they are not road legal.
 

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Race cat. Most 100cels you will find will be FIA approved. There will be no difference in performance due to the internal design of a race cat. Then there's no worry at MOT time or on the spot VOSPA checks. There's also plenty of cars running big power with race cats.
 

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Discussion Starter · #7 ·
If the performance is just as good with a race cat then i would rather go that way, i have to be a bit carefull regards noise as still run parents ( 80 yr olds) to London several times a year, hence 5 dr ST and not an RS at the moment. so its all about preformance with reasonable noise levels
 

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If the performance is just as good with a race cat then i would rather go that way, i have to be a bit carefull regards noise as still run parents ( 80 yr olds) to London several times a year, hence 5 dr ST and not an RS at the moment. so its all about preformance with reasonable noise levels
There will be negligible difference between a 100cel race cat and decat.
A race cat will be quieter if that's a factor for you for sure.
 

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For the noise reasons alone, a decat. However I'm going to have to swap mine for a race cat come renewal as Greenlight will not cover them.
 

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For the noise reasons alone, a decat. However I'm going to have to swap mine for a race cat come renewal as Greenlight will not cover them.
I thought not that long ago Greenlight said they would cover decats, has there been a recent change do you know?
 

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They refused to cover one for me when I renewed in April mate, otherwise I would have gotten a decat.
Maybe I'm wrong then Alex, doesn't affect me directly as I have a race cat but I remember there being a big debate on this a few months ago. It might not have been green light that said they would cover a decat though, can't find the thread now.
 

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I have been using a 100 cell FIA race cat for 4 years now.....no crawling around under the car come MOT time , no worrying about insurance issues should you be involved in an accident or as Adam says , Mr plod having a bad day and wanting to have a look for himself !!
 
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