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Discussion Starter #1
I currently have a 3" de-cat system but got black flagged at Donnington for being too noisy. Considering I'm planning a Ring visit, I thought it might be wise to do something about it....

So, the issue is that I have a twin rectagular tailpipe so I assume unless I can find someone to fabricate a removable baffle, its a new back box. Given that the seam on the back box has split as well ( although could be welded ), I'm quite open to this but don't want to spend a fortune.

Any ideas guys before I hunt second-hand as well ?

I don't want a permanantly smaller opening as I do like the sound and assume performace is reduced in some way....

Thanks,
 

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hi v8guitar,
well you could try an apexi exhaust butterfly valve! i have one on my r34 gtt, you control it by a switch in the cabin ( sport or silent ) cool bit of kit :chuckle: not sure where to get one like! and you dont lose any power wiv it, only thing is not sure if it wud fit your setup:confused: but you cud look into it, well hope this helps a bit mate. cheers marty.:)
 

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Blitz got an exhaust system which is at 96db with a baffle, which is quite good (I'm talking about the 96db)
I don't know if a high flow cat would be less noisy than a de-cat. pipe, if it's the case that could help as well
 

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hi there....
dont worry about it for the ring. i have a 4-5" straight through system registering 105db and i had no problems at the ring.
trick is to pull away sedately from the barriers... take it fairly easy (ie. revs under 5k) untill you have passed under the 1st gantry and rounded the first 3 corners, then fooking nail it!!!!

no probs.
 

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hi v8guitar,
well you could try an apexi exhaust butterfly valve! i have one on my r34 gtt, you control it by a switch in the cabin ( sport or silent ) cool bit of kit :chuckle: not sure where to get one like! and you dont lose any power wiv it, only thing is not sure if it wud fit your setup:confused: but you cud look into it, well hope this helps a bit mate. cheers marty.:)
careful with them..my mate had one on his 32 and when the butterfly valve is closed (quiet) and you give it some, it shattered his turbo's due to the pressure build up
 

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thanks faz my mates say i drive like miss daisy:) lol so i should be ok on that one. cheers for the info marty.
 

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Discussion Starter #8
hi there....
dont worry about it for the ring. i have a 4-5" straight through system registering 105db and i had no problems at the ring.
trick is to pull away sedately from the barriers... take it fairly easy (ie. revs under 5k) untill you have passed under the 1st gantry and rounded the first 3 corners, then fooking nail it!!!!

no probs.
I am worried because I think you were lucky. If they see a modified car, they often ask you to rev it....so just didn't want to take the risk if I can avoid it.

Thanks to everyone for all the info, as my exhaust isn't a standard item, I may have to change it first anyway...

Faz - I love your avatar!! Cracks me up everytime I see it!!
 

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Discussion Starter #9
So, I think I have a solution! After talking at length about the options of changoing the back box, the whole system etc, Garth from MGT came up with a very simple solution ( so simple I can't believe I didn't think of it)....its a twin pipe job, so block one of the pipes..

Result 104db reduces to 93db!!

Doh!!! That will do for the short term!

Thanks again for everyones replies!
 

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93db is very good! I thought it was quite loud at the beginning (got 93db on my civic coupe) but after driving the Skyline non stop for 2 weeks, 93db is definitely quiet!
 

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yes your right to worry about noise at the ring ,thay do random noise test at the barrier ,i got pulled in april,tested then turned round:bawling: there getting strickter,it is a bit pot luck if you get pulled for a test,but it,s a long way to go to be told you cant run your to load:bawling: i was,nt to bothered as we only dropped in at the ring on are way to spa for a track day:chuckle: NISMOMAN
 
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