Noise testing: what classes as max revs?
Discussion
LooneyTunes said:
Very quick one: if the car has a rev limiter set some way below the theoretical max RPM of an engine, which will the tester accept as the relevant figure when calculating the noise test RPM?
Thanks in advance for any thoughts.
er no its too easy to alter the setting later; its the redline x .75, if there is no redline, the tester will normally have an idea of the required rpm. Remember that is just the static test most circuits have drive by at multiple locations too.Thanks in advance for any thoughts.
It's lack of redline that is causing the problem (it's a Westie so has a different rev counter to the original) - would they accept the original redline of the donor vehicle even if it is obvious some work has been done on the engine?
Problem I have is that I didn't commission the build and have no idea quite how far it can be pushed (not to mention preferring to avoid finding out the hard way!) but don't really want them assuming it is a full race spec build and choosing the rpm accordingly.
Problem I have is that I didn't commission the build and have no idea quite how far it can be pushed (not to mention preferring to avoid finding out the hard way!) but don't really want them assuming it is a full race spec build and choosing the rpm accordingly.
I would use the standard redline data and depending on the limit and reading together with a comment as to how the static is only part of the test, and that if you push it and get a black flag you know why!
Remember if you have a repackable type side sliencer fitted they do need to be repacked regularly with either glass wool or wire wool depending on spec. Telling the tester it was only 97 last week at Snet before doing a whole day wont wash if its clearly 102 at test!
Remember if you have a repackable type side sliencer fitted they do need to be repacked regularly with either glass wool or wire wool depending on spec. Telling the tester it was only 97 last week at Snet before doing a whole day wont wash if its clearly 102 at test!
Due to location it's mainly going to be Oulton, which is conveniently 105db, and Anglesey. Perhaps Donington too if I spot a convenient day at 105+ - have doubts about getting under 95/98dB (unless I can find a much bigger exhaust for track days) but will see what she's like when the can is repacked.
In my experience (with my Striker, so instruments with no red line etc) they ask what my max RPM is, I tell them and they test it accordingly.
I guess if you said something so low that it sounds silly then they might question it, but I've never been asked what engine it is and definitely nothing about state of tune etc.
105db is really loud btw, doubt you'll have any problems at Oulton. Anglesey don't do any noise testing (at least not on noisy days, I've noticed that some TDOs are running days with lower noise limits there now and I don't know what happens with those).
I guess if you said something so low that it sounds silly then they might question it, but I've never been asked what engine it is and definitely nothing about state of tune etc.
105db is really loud btw, doubt you'll have any problems at Oulton. Anglesey don't do any noise testing (at least not on noisy days, I've noticed that some TDOs are running days with lower noise limits there now and I don't know what happens with those).
Oulton is great in a Westfield and one of the more generous limits, if you aren't sure about your noise levels and you are local then it's worth taking the car down when there is a trackday on and they will be happy to test it so you know your current score.
As an alternative, you couldn't do better than coming along to the WSCC trackday at RAF Cottesmore on Aug 26th - INFO HERE. Open pit on a 3 mile circuit and there's also a timed 1/4 mile available in the morning and timed slalom in the afternoon. Only open to Westies, se7ens, Elises etc, no tin-tops!
As an alternative, you couldn't do better than coming along to the WSCC trackday at RAF Cottesmore on Aug 26th - INFO HERE. Open pit on a 3 mile circuit and there's also a timed 1/4 mile available in the morning and timed slalom in the afternoon. Only open to Westies, se7ens, Elises etc, no tin-tops!
Yes - Oulton should be fun, parkland circuits always hold a greater degree of interest.
Sadly Cottesmore is probably out this year due to work commitments, but would be interesting to do a Westfield day at some point - if only to kick a few tyres, see what everyone else is running, and pick up some idea for future mods.
...and yes, she is loud enough to worry about 105 being an issue - may buy one of those meters linked to in the other thread just to see what it reads or run down and have a proper check.
Sadly Cottesmore is probably out this year due to work commitments, but would be interesting to do a Westfield day at some point - if only to kick a few tyres, see what everyone else is running, and pick up some idea for future mods.
...and yes, she is loud enough to worry about 105 being an issue - may buy one of those meters linked to in the other thread just to see what it reads or run down and have a proper check.
Reassuring!
By the way, MSV seem a little vague about what will get you pulled off in terms of drive-by at Oulton simply saying that:
By the way, MSV seem a little vague about what will get you pulled off in terms of drive-by at Oulton simply saying that:
Oulton Park's website said:
If the results of the drive-by monitoring show that a particular vehicle is generating drive-by sound levels appreciably higher than vehicles with comparable static test results, then MSV staff will notify the participant, and the relevant vehicle shall not be permitted to take further part in the event until the participant has addressed the noise levels generated by their vehicle to bring them within acceptable sound levels.
Does anyone have any insight into what this means in practice? (i.e. what is "appreciably higher"?)Unless you are very close to the static limit or have a disproportionate noise under load (usually this is weird forced induction kit) you shouldn't have a problem.
105 is very achievable on a se7en unless you have a decent silencer, my dura used to make 103-104 until I got a re-packable unit made for it.
105 is very achievable on a se7en unless you have a decent silencer, my dura used to make 103-104 until I got a re-packable unit made for it.
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