Has anybody passed a drive by test at Bedford with a CSR?

[PipeNslippers]

I am thinking of going to Bedford Autodrome for a track day with a CSR260, but they have a drive by noise limit of 87.5db..at 20 metres..

I am having a RaceCo silencer fitted as the standard silencer has a static noise test of 102.5 db...which would fail the static test of 101 db straight away.

What are the drive by noise levels like for a CSR260 fitted with a decent silencer..I understand intake noise is also a major issue?

[Dave J]

sounds like it needs a silencer repack ?

it's not unusual to have circa 95db for a duratec . My 2.0L is circa 96db with my home made 6" x 27" silence at 4500rpm at 1m at 45degrees - even at castle Combe !

[harry b]

I got a raceco exhaust on my EFI 2.0XE with similar setup as a R500, which had static 92Db
Induction noise is the biggest issue on my car. Allthough it sound very loud, it still is below 96Db.
The pitch of the sound contributes also to reduction of Db. A quitly sounding low noise V8 can be noisier in Db value than a much higher pitched ear pounding induction noise.
I was very suprized that my car passed with the induction noise on local tracks where 95Db is the limit, measuring at a bit greater distance than the 1mtr

Edited by harry b on Friday 15th June 12:05

http://www.youtube.com/watch?v=jNbi0BBQ4k4&fea...
At around 3:32 and 5:25 you can hear clearly the intake noise of my car, no exhaust noise at all.

Edited by harry b on Friday 15th June 18:17

[PipeNslippers]

harry b said:

I got a raceco exhaust on my EFI 2.0XE with similar setup as a R500, which had static 92Db
Induction noise is the biggest issue on my car. Allthough it sound very loud, it still is below 96Db.
The pitch of the sound contributes also to reduction of Db. A quitly sounding low noise V8 can be noisier in Db value than a much higher pitched ear pounding induction noise.
I was very suprized that my car passed with the induction noise on local tracks where 95Db is the limit, measuring at a bit greater distance than the 1mtr

Edited by harry b on Friday 15th June 12:05

http://www.youtube.com/watch?v=jNbi0BBQ4k4&fea...
At around 3:32 and 5:25 you can hear clearly the intake noise of my car, no exhaust noise at all.

Edited by harry b on Friday 15th June 18:17

I have found my answer in another forum:

http://csr.informe.com/forum/bedford-autodrome-and...

So with a decent silencer it looks like we are good to go with a CSR260..based on actual experience.

[PipeNslippers]

PipeNslippers said:

I have found my answer in another forum:

http://csr.informe.com/forum/bedford-autodrome-and...

So with a decent silencer it looks like we are good to go with a CSR260..based on actual experience.

Update:

Just completed a (wet) Track Day at Bedford and it was fantastic..loads of run off area..gives you huge confidence to explore the limits...which I did and beyond...

No noise problems with the CSR260 fitted with a RaceCo race silencer and a Cat Bypass pipe.

Went from 102.5 db with the standard silencer and Cat to 92.2 db with the RaceCo set up..

The car was fantatstic and I had an instructor for the day..who has been in many Caterhams.

He could not get over the torque..there is no need to take the engine over 6,000 rpm to be quicker than anything else on the circuit..and you still have an extra 2,000 rpm to play with if you need it..

The engine never got hot or bothered..to be honest it is wasted on the road..and I realised afterwards that I did not even floor it for the whole day because I could not get enough grip in the first three gears..!