Noise impact of cat removal on a Sigma

[heptagon]

Does anyone know if the cat removal makes much noise difference on a Sigma 270?, I haven't noticed much difference on mine.  I ran with a cat at Castle Combe last year and am there next week but recently have run without it and wondered if there's any likely noise test risk?

[W33SVN]

I'd agree with you. I went the other way and put a cat on, not a huge amount of volume difference. Maybe a slightly flatter sound if that makes sense, not quite the same angry bark. 

[Toddler]

I used to have a sigma roadsport 140bhp without a Cat.

Always passed the noise test.

On one occasion at Bedford they suggested I short shifted at certain corners but I'm pretty sure they confused me with another car as I had been there many times without issue.

[150SV]

I ran decat pipe on my 150 for while, its a sharper note but I dont think its any louder.

I took mine off for MOT and found it ran better with cat so sold my decat on.

[krisfl]

My sigma passed easily at Castle Coombe with its decat pipe on. It's a 100db limit there I think. I came in around the low 90s. You should be fine. I'm there tomorrow too. 

[heptagon]

I left cat on in the end (ran out of time to remove it) and mine was 93 at CC so way below the 100 limit, so I'll know for my next visit