52 replies to this topic

[smiley]

My other concern is noise limits for 'quiet' track days.

 

Join the club

 

Another recommendation is the db killers that tullett can build you. They are of good quality. I Always have 1 in on track days (every bit helps) as 2 x 3" end tips functioning as trumpets is not helping with the noise issues.

 

But in the end noise is a very difficult topic on high power SC systems.

Edited by smiley, 28 May 2015 - 09:57 AM.

[Exmantaa]

After the Dutch broke a few tullett cat sections (default is magnaflow ceramic ones i think), we feel it's best is to spill a bit extra, and ask tullett to build in the HJS cat (which is steel and can handle the SC heat better), like Chris mentions. This is regardless if you choose a 2.5 or a 3" system.

 

 

 

The standard Tullett cat section is a 200 cel metal version. (Can be Magnaflow, no idea but it's a cheap one and will self destruct on anything bigger than a Stage 2 SC... 

 

The standard cat is well made, you shouldn't have an issue with it as long as you're not running very rich.

 

Standard ceramic OEM 2.2 cat or the cheapo standard Tullett one?  

[Exmantaa]

ps; the downpipe silencer/cat section makes a BIG difference in noise levels. (and also on the logevity of the silencer stuffing...)

Endpipe trumpet shapes also make a difference. I use a straight single tip.

[tommobot]

You must be the 5th car around here now! Good luck in the search. Tommobot has an SC though his is far from standard.

 

Yep, I'm from Stratford. Loads of us round here now!

 

At the moment its SC'd on standard manifold, with a standard downpipe with precat & decat removed (welded back up) and a 'modified' standard turbo backbox. Noise wise, it isn't tooo bad, infact I'd classify it as quiet. With the standard cat section in it was near silent bar intake noise. Unfortunatly can't give any relative noise level reference but your more than welcome to come and have a nose...

[pete-r]

I have a standard manifold, decat and larini if you want to try it but I'm in swansea.

  I had a Larini on my last NA. Loved it. But I imagine it'll be effing loud when combined with twice as much exhaust volume and a howling supercharger on top!   Do you ever get it on track? Any idea of drive-by noise levels?

I've no idea of the noise level but I've never had an issue so far on road or track...

Edited by pete-r, 28 May 2015 - 12:50 PM.

[MartinS]

Most of the sc noise is through the air filter and on drive by's not static. If its enclosed most can pass most sounds checks. (Piper VM7000 works well on mine when I need it

but there is also a specially designed ITG I believe) Your welcome to look at my set up but am a long waya away in sussex.

 

Martin S

 

[Mr Apex]

I use this air filter system on my SC - works well and is very quiet. 

[pete-r]

I use this air filter system on my SC - works well and is very quiet. 

What car model is yours meant for? Assume not an NA?

[cressey]

I'll just leave this here. http://www.vx220.org...tial-group-buy/

[Rosssco]

The SC I just bought has a standard manifold, some variety of 2.5" mid section and high flow cat, and tubby rear box. It has some low frequency noise (in a good way), but really relatively quiet and just the right side of standardish. And would be totally suitable for track work, without hurting any performance at stage 2 level.. Sound from inside the cabin (not me driving I should note ) where clearly the SC is the dominant noise..

[Mr Apex]

 

I use this air filter system on my SC - works well and is very quiet. 

What car model is yours meant for? Assume not an NA?

 

My car is a Stage 2 SC, with original throttle body. When I bought the air filter, it was labelled on the Demon Tweeks site as universal. The part code at Demon Tweeks was K/NRC-5052AB. With the Tullett and this filter, my car makes 252bhp at 6500rpm and 234ft-lbs torque with the Courtenay map. I drove it at Castle Combe on several track days and had no problems with static or drive by noise.

[pete-r]

Is that the 68mm LSJ tb? I'm currently running the pipercross cosworth filter on the LSJ body. Id consider a change for better filtration rather than any noise issues.

[Mr Apex]

I started with the 68mm TB, but changed to the stock TB later - the 68mm was faulty. Either will work with that filter system. The 68mm gave a couple more bhp, but not enough to justify getting a new one.

[DaveyC]

Thanks for all the input chaps.

 

I went over to Milton Keynes last week to have a look at techieboy's 3" Tullett, which wasn't as loud as I was expecting. I've decided to go with that setup but chickened out and got an HJS cat instead of a silenced decat.

 

Closed air filters are certainly something that's in my mind to take along as a backup should the car fail any noise tests.

[FLD]

got an HJS cat instead of a silenced decat.

 

 

 

Get both and have them made as a bolt in swap.  Thats what I have.  I run the decat silencer most of the time to make the whole thing acceptable.  With the cat it does droooooone on a bit.

[DaveyC]

That was my plan but they wanted £750 for the decat.

[FLD]

Oooof!

[mxorvx]

The SC I just bought has a standard manifold, some variety of 2.5" mid section and high flow cat, and tubby rear box. It has some low frequency noise (in a good way), but really relatively quiet and just the right side of standardish. And would be totally suitable for track work, without hurting any performance at stage 2 level.. Sound from inside the cabin (not me driving I should note ) where clearly the SC is the dominant noise..

Sounds like a phantom

[JG]

 

got an HJS cat instead of a silenced decat.

 

 

 

Get both and have them made as a bolt in swap.  Thats what I have.  I run the decat silencer most of the time to make the whole thing acceptable.  With the cat it does droooooone on a bit.

 

 

Do you not get a lambda fault with the silencer section in?

[DaveyC]

Bit of an update - it is now on the car and has been for a few months.

 

It is a bit droney with the HJS cat, but the most irritating thing is the rattle as the silencer and cat vibrate against each other - the HJS is too fat to fit properly.