Croft Noise Limit

Will supersports exhaust with crp be ok for croft or would it be best to refit the cat? The exhaust has done less than 1k miles so is about as new.
Thanks for any help


From what I gather you should be okay…but to be sure it would be best to refit the cat - or buy a silenced de-cat pipe from Eliseparts.

So what’s going to be the noise limit on Croft?

I am saying because I have no idea of how loud my new exhaust would be on track, this would be the first time out for it.

Okay Peeps, I’ve just phoned the circuit.

Limit is 99db, static from 1/2 metre.

Maybe it would be a good idea for everyone to reduce the rev limiter, as it’s usual for the noise to be tested at 2/3 max revs

Fcuk! I’m sure mine is going to be borderline.
What about drive by noise? are there going to be microphones at the track? or only initial testing?


Per the email sent by Croft to Tracksport: max noise, which will be monitored throughout the day, is 100db static.

So, it looks like we’ll have to limit our cars at 7000rpm, so the test will be at around 4700rpm.

How does this compare with Bedford? I passed there but not sure by how much…


To put my mind at ease … does anyone have the required equipment to test our static noise levels before we get to croft ?

This will be my first trackday in the Exige so i have no idea how loud my reading is likely to be … would be more than a shame to drive all that way to be told the car is too loud

How does this compare with Bedford? I passed there but not sure by how much…


Bedford is VERY strict so if you pass there you’ll pretty much pass anywhere else (except maybe goodwood )

I’m in the same boat as 6970K (Janspeed exhaust). I know the SCRP will reduce the noise by about 3db but anybody know if this will bring it under the requirements?

Thanks Rob. To be on the safe side i think will get the cat put back on.

To put my mind at ease … does anyone have the required equipment to test our static noise levels before we get to croft ?

Yes, I’m on the A33 between Reading and Basingstoke, feel free to pop over, PM me. There seems to be a constant stream of Exiges outside my house having their noise checked!


ive got the oval Janspeed exhaust on mine with no cat, i got tested at 1 meter away 3250 rpm at 104 db. I thought and got told by the company organising it when i booked it was going to be a 105db day. How many db will the standard exhaust knock off my reading? i dont have a cat to put on only the standard exhaust.

I have a noise meter if anyone wants to test theirs in Kingston , Surrey. Mine with a cat pipe and Eliseparts exhaust reads at 103db at 5250rpm (3/4 revs) at 1/2 metres away from the exhaust if it helps. I would have thought you would definately need a cat / silenced cat pipe to get under 100db.

As far as I remember from high-school and the stuff I learned on noise/sound and stuff.

ANY DB-measurement should be performed at 1 mtr distance in-line and at 45degree angle of the sound-source. The 45-degree measurement is only required for sound-checking etc to check cross-over and feedback noises, but for the purpose of car-testing : Directly in-line with the exhaust-pipe. If the exhaust points upwards : you must keep the Db-Meter higher then the exhaust itself, if it is level at the same height of the ground as the exhaust, etc…

IMHO a “static” test does not tell much at all about the noise a car makes. The car is unloaded and “free-revving”. Under hard-accelartion a car is likely to make a different type of noise and as such gives a complete different read-out then what you would get when static.

A drive-by test (controlling agent driving) or rolling-road test is the only sure way to measure the noise a car makes.

This point has been raised a few months back in an issue of EVO. It also mentioned the difference between similar engines : low-frequencey scream, high-frequency scream. Objectively as noisy, subjectively worlds apart.

i just phoned Tracksport or whatever there name is. They just told me its a 100db drive by test. Which should be a bit better than static testing for me.

Tested my S1 Exige (190) with janspeed today… At 5700 rev the noise was 104 dB without CAT… I then fitted a normel CAT and the noise went down to 99 dB… So Ill keep the CAAT on …

I have a ‘ticket’ showing 101 Db driveby from Donington…

Told them I adjusted my boost, and drove past the meter on half throttle in 6th for most of the day !!!