Exhaust Decibel Limits

[Tiamat]

Does anyone know what the decibel limits are for a track day?
Don't think mine is crossing the limit yet but don't want to risk losing money by being told I can't go out on the track.
Also, anyone know where you can get your decibel limit tested? Do local councils provide anything like this or can I take it into ATS or something like that?
All help appreciated.

[Slacey]

Anywhere near Telford on Sunday?

I am conducting a noise test of various MK3 exhaust systems (along with my own MK3 turbo) with BenF, so if you can make it you are welcome to tag along and have your system measured.

[spag]

Castle Coombe limit is 100dB, strictly enforced, but I don't know about other places.


Spag

[Lauren]

db limit depends entirely on the circuit.

Elv is 105db for example
Donny is 98db driveby.

Combe is 98db measured 0.5m from exhaust tip at 3/4revs.

I'd aim to get it not more than 95db if you don't want any probs at the track.

You can measure the way combe do with a noise meter. You can't really measure what it'll be driveby though.

My old SC for example with a magnex measured 84db @4500rpm 0.5m from the exhaust. that was pretty quiet.

As you have a MK1 i'd recommend mangex/mongoose if you don't want any probs. Janspeed should be avoided.

[Tiamat]

Cheers Slacey, but am in Hampshire and kinda committed this weekend, thanks anyway.

Already have a Powerflow exhaust system fitted, which appears to be louder than the Mongoose system, and just want to be sure before taking it on the track. Also, have been stopped by the rozzers for the noise it makes and want to make sure its not going cause me any future problems.

Lauren, by the way have you ever had problems on a track day with engine damage? My MK1 has just over 170,000 on the clock on the original engine and gearbox and am concerned that it won't stand up to the "thrashing". Is there anything I can do to it before going out on the track to help protect it?

Thanks.

[Lauren]

Cheers Slacey, but am in Hampshire and kinda committed this weekend, thanks anyway.

Already have a Powerflow exhaust system fitted, which appears to be louder than the Mongoose system, and just want to be sure before taking it on the track. Also, have been stopped by the rozzers for the noise it makes and want to make sure its not going cause me any future problems.

Lauren, by the way have you ever had problems on a track day with engine damage? My MK1 has just over 170,000 on the clock on the original engine and gearbox and am concerned that it won't stand up to the "thrashing". Is there anything I can do to it before going out on the track to help protect it?

Thanks.

So far i've never had a mechanical problem apart from daft things like losing a gear cable clip and blowing a boost hose off.

If your engine and box are in good condition there really is no reason to suggest that they won't stay that way. I did 30+ trackdays in my SC and never had an engine fault or suffered any damage.

There are sensible precautions you can take, like checking the oil and coolant before you go. also check the oil after the first session and again at lunchtime. You soon see whether or not you will burn any oil. In the end with my old car sometimes i wouldn't check the oil all day as i knew it would be okay. I simply drove on track came in got out of car, then back in for the next session. No worries at all.

At the end of the day all you are doing on track is driving your car harder than you do on the road, thats it. There is no requirement to redline the car in every gear on every session you go on. You can take it easy if you want. Also i tend not to hammer the brakes as there's nothing to be gained from this seeing as trackdays aren't timed.

I generally tend to change up at 7K, pretty much all the time on track unless a given corner dictates a short shift.

HTH

[Tiamat]

Thanks a lot Lauren. Will do as you recommend.
Was concerned about damage to motor, would be devastated if my baby got ruined.
T

[Lauren]

Thanks a lot Lauren. Will do as you recommend.
Was concerned about damage to motor, would be devastated if my baby got ruined.
T

No worries. Honestly if you approach a trackday sensibly you should have no problems. If you do have a mechanical problem it would have happenned anyway. So if your car is in good nick mechanically there is nothing to fear. Doing things like a good cool down lap also help.

If you come on the IMOC day in sept then there will be plenty of experienced people there to offer you tips and advice.