Engine Speed for Static Noise Testing?

[Pickled Piper]

I was at Oulton Park last week.My vehicle was static noise tested and during which I was asked to hold the engine speed at 5200rpm, which I am assuming was based on a percentage of the total rev range (approx 75%). On other track days I have attended all vehicles were tested at 4000rpm irrespective of total rev range.

Can anyone explain if there is a standard for defining the engine speed for static noise testing or does it vary from circuit to circuit?

Cheers pp

[JeffC]

I was at oulton also , told them i red lined at 9k and they made me rev mine to 6750 100db , they did say 3/4 of max revs to be fair ... every other track ive been to have asked me to rev to 6k.

they are maybe better at maths than other track organisers

[F355GTS]

Donington - Driveby, may have changed haven't been for a while
Castle Combe 4.5k revs
MSE Days 4.5k revs, except bike engines at 3/4 max
Goodwood 3/4 max revs
MSV Brands 3/4 max revs
Silverstone Never seen a test

[Pickled Piper]

Cheers Guys.

it's starting to make some sense now.

pp

[silv]

Pickled Piper said:

Cheers Guys.

it's starting to make some sense now.

pp

In my experience most marshals are not too strict and lets be honest probably don't know what your maximum engine revs are anyway. IMHO noise limits make no sense at all !! A race track is a race track and will always create noise. The planners and the numpties who live near our race circuits are a pain in the butt! If they don't like the noise they should not live near a race circuit.

Edited by silv on Monday 4th June 11:29

[Zumbruk]

silv said:

Pickled Piper said:

Cheers Guys.

it's starting to make some sense now.

pp

In my experience most marshals are not too strict and lets be honest probably don't know what your maximum engine revs are anyway.

Quite. They usually ask what your max revs are anyway - tell them what you like. For MSA events, they measure at 2/3 maximum. My rev counter was broken at an event recently & the bloke said "just guess." And at a track evening last week, I just ran it up to decent-ish revs and the bloke was quite happy.

silv said:

IMHO noise limits make no sense at all !! A race track is a race track and will always create noise. The planners and the numpties who live near our race circuits are a pain in the butt! If they don't like the noise they should not live near a race circuit.

Depends who was there first. If you move adjacent to an existing facility, then STFU, but if the facility appears after you move in, then you may have some grounds for complaint. OTOH, I don't have a great deal of sympathy for the the people who complain about Bedford Autodrome, given that it's way quieter than when it was an MOD research airfield, and one of the possible alternative uses before Palmer bought it was as a TNT Skypak cargo hub, which meant there'd be cargo 747s landing every few minutes.

[Pickled Piper]

silv said:

Pickled Piper said:

Cheers Guys.

it's starting to make some sense now.

pp

In my experience most marshals are not too strict and lets be honest probably don't know what your maximum engine revs are anyway.

Edited by silv on Monday 4th June 11:29

I agree. Most marshalls that I have come across have been helpful. However, I don't want to become reliant on this and then find one day I'm sent home. i think I may invest in a bolt on tail pipe type silencer. The trouble is it's a 911 with twin tailpipes so it looks like I will have to buy two of whatever I need. Any reccomendations for a 911?

pp

[twinspark]

Unless you've deliberately gone out to buy a noisy exhaust, I can't see it being an issue on a 911.

TVRs sound bloody loud as standard and seem to pass the tests OK, as do Caterham-types with little more than carbon bike silencers on them.

Of course, the chav 2 doors down from me with his Clio wouldn't pass a test, as he appears to think it's cool to have an exhaust you can hear from half a mile away.....

[muckymotor]

Elvington is a 103db static test which a couple of cars failed last time I was there including a 911 which didn't sound loud at all to the ear. They've also just introduced a 95db limit when out on the circuit.

[BobM]

muckymotor said:

Elvington is a 103db static test which a couple of cars failed last time I was there including a 911 which didn't sound loud at all to the ear.

I think the problem with 911s is that when they do a static test the mic picks up all the mechanical noise from the engine which is a problem particularly for older cars.

[JeffC]

engine noise is my argument on my bec, the exhaust is on the side so when they check it it picks up a lot of engine vibration, If you dip the clutch it can be quieter , Ive proved this is the case by putting a plasterboard beside the car and checking the levels again and the noise drops considerably when its only getting exhaust noise . you dont have this problem on a tintop with front engine and rear exhaust.

So maybe I could get the tub of my car dry lined and plastered or put a link pipe from the can under he car and out the rear of the car I would pass without a problem.

[BobM]

JeffC said:

So maybe I could get the tub of my car dry lined and plastered or put a link pipe from the can under he car and out the rear of the car I would pass without a problem.

True that there's a lot of noise from a bike engine, lot of induction noise too - some of the guys do lag the engine bay with sound deadening material. For the drivebys fitting an airbox reduces the noise a lot too.

[BertBert]

F355GTS said:

Donington - Driveby, may have changed haven't been for a while
Castle Combe 4.5k revs
MSE Days 4.5k revs, except bike engines at 3/4 max
Goodwood 3/4 max revs
MSV Brands 3/4 max revs
Silverstone Never seen a test

Except at CC in a Rad, the noise man wants 3 yellows which is 7k rpm.
Bert

[silv]

And did you pass!!