[/quote]
I should know on Monday when I’m getting it back - hopefully weekend after next.
Mike [/quote]
Just in time for the Hot marque’s trackday at KH
Dave
22nd April is fine, ill be there. Has a price been talked about yet for the track day? How strict is this 98db drive by? Whos the guy with the Mclaren Exige? i saw him at Donnington with a long pipe on the end of his exhast, i assume to keep the noise down! If you read this or if anyone else can help where do you buy them from?
Does anyone know what sort of noise level an Exige fitted with sports exhaust and cat bypass pipe would be, and if its over 98db would refitting the cat get it through the noise test.
Cheers
Dave
Does anyone know what sort of noise level an Exige fitted with sports exhaust and cat bypass pipe would be, and if its over 98db would refitting the cat get it through the noise test.
V.probably and probably.
Ian
Just in time for the Hot marque’s trackday at KH
Dave
Dave,
When is it?
Also get yourself a silenced cat bypass pipe it will save you all the hassle of swapping them over for certain track days
Mike
Ok guys I’m getting dead confused over this noise issue, especially the drive by.
I have an S2 and on the log sheet it quotes these figures for noise, this is with standard exhaust as supplied by Lotus.
Stationary 98dB(A) @ 5850 rpm with a drive by dB(A) of 74 (what rpm??? don’t say).
OK so far not so good.
If it’s a drive by would this not differ wildly from how far away the level was checked at? Also would it have an effect as to how built up around the area of the noise check it was regarding reverb etc?
98dB sounds at lot for a drive by even with a sports exhaust without cat (S1 or S2) when a standard S2 is quoted at the 74 dB(A) mark.
To throw another spanner in the works dB and dB(A) are two different measurements/notations (if I remember back to my college days) and I need to get my notes out to swot up on this, unless (I’m sure we have) there is an expert out there. It’s all just so confusing to me and it’s no good once you get to the track day and get slung off for being to loud. I have a noise meter and if anyone around my neck of the woods wants me to check their car out I am more than willing to help out.
I think we need a few guinea pigs with spare exhausts and spanners at track days to sort this one out.
As an aside, Uncle Pesky, I was down provisionaly for the Croft track day but had a text whilst away skiing and I may be called out to the far East to help with the rebuilding of the comms infrastructure, will know more when I get back to work Monday and will call round to have a chat/beer etc Monday or Tuesday evening if thats Ok, I would say poss 3 to 6 months contract to get things in motion, so I may have to rain check Croft .
John
Not completely sure in the (A) business, but I believe there are two measurements type A and C. One only measures audible vibation. Sorry, not much help, but it may jog your memory.
Ian
Ian
The A and C regard the weighting characteristics/ how the noise meter responds not the dB notation.
I.E.
(A) weighting = range 500 to 10,000 hz range (Human ears most sensitive range) you would use this to determine an area’s noise level, taking several readings around an area.
(C) weighting uses flat freq characteristics 30 hz to 10,000 hz range mostly used for measuring musical sound levels, ie setting up your hi-fi/surround sound set-up.
Not sure even with this info which weighting the guys at track use, A or C? Who’s on a track day soon and could ask the noise checkers.
John
Jaycee
Behave, & stop fretting over nothing
Your car was noise tested at Oulton in December, & the Noisemistress didn’t bat an eyelid, once she realised that your’s was the [color:“pink”]cute [/color] “all singing & dancing” S2 version of
[image]http://www.homeandgardening.co.uk/hairdryer.jpg[/image]
So you’ve not got owt to worry about
![http://www.homeandgardening.co.uk/hairdryer.jpg[/image]](http://www.homeandgardening.co.uk/hairdryer.jpg%5B/image%5D){kind=link}
Would be great to provide you with a beer or two tomorrow evening - hopefully my empty garage space will be no more
Jaycee
Behave, & stop fretting over nothing
Pesk, not fretting just would like to understand things a little more, college was 30 years ago and a few bottles of beer and wine have passed my lips since then!!
Your car was noise tested at Oulton in December, & the Noisemistress didn’t bat an eyelid, once she realised that your’s was the “all singing & dancing” S2 version so you’ve not got owt to worry about
But Uncle that was only because you remembered where the red line was before me
Would be great to provide you with a beer or two tomorrow evening - hopefully my empty garage space will be no more
I hope so, if only to stop the ‘naggin tackle’ asking me ‘is Rob’s car back yet’. Think she maybe wanting to check out if the S1 is more comfy/cuter than the S2
John
[image]> http://www.homeandgardening.co.uk/hairdryer.jpg> [/image]
Hell, you even found the correct colour of hairdrier although the diffuser needs some work for optimum effect
jaycee
you are right but mislead yourself a wee bit… I just had a quick look at some Sound Engineering books (i used to do sound engineering) to refresh my memory…
dB(A) is the “A filter weighting” like you mentioned. Also sometime just dBA… i think SI recommend using dB A (ie with a space and no brackets).
Anyway, agianst the weighting scale “A” which, like you say is for the range where human ear is most sensitive (something like 1kHz-10kHz) the measurement will be relative to 1 picowatt or 0.02 millipascals which for sound is where the 0 dB point is (not detectable by the human ear)… you will already know that decibels are ratio’s on a logarithmic scale so the 98dBA figure usually of interest to us is a measured sound pressure level (SPL) in the range 1kHz-10kHz relative to 1 picowatt. This is what Trackday nazis will be using… every 3dB increase is 10 times the power or twice the relative volume your ear hears…
Does that make sense ??
Does that make sense ??
Found my notes and now nothing makes sense
Lot’s of talk about dBm dBm0p dBr dBmp dBc dBu and more!!!
Think I leave this thread at ‘if it’s too loud they will chuck me out’ and write a thousand times you must not go on the Exiges board when you have had more than a bottle of wine
John
LOL…
I don’t recognise some of them but like Einstein says…its all just relative …
We want dB A, for our purposes tho.
Think she maybe wanting to check out if the S1 is more comfy/cuter than the S2
John
That’s obviously yes isn’t it
Having just noise tested Turner’s car (Eliseparts + Sports Cat = 106dB ) it must be dB weighting A, as C was almost off the scale at tick over.
An interesting tip, it dropped a dB or so once it was warmed up.
Ian
I was noise tested at Oulton yesterday - Da Edwards Silencer plus Eliseparts silenced de-cat = 97db (at 4800rpm). No public comment on rpm please
Have fun on track with the Honda?!
Ian
Have fun on track with the Honda?!
Ian
As usual at this time of year Oulton was somewhat slippy! Just popped down for the afternoon to touch base with the chaps from Tracksport, & they suggested that I have a few laps I took it nice & easy, & Russ had a few laps out in his Gaylardy.
Today, we’ve both been to Anglesey - well pleased with my car Russ drove it for 1/2 hour too, & he seemed to like it also JohnO also turned up for a “spectator session” in his new car - a stunning black Gaylardy
Thanks for the drive, Dad. I was so impressed with Pesky’s car, it is a real peach. Having driven his car just before and after the conversion, the Honda feels so much better, pulling like John Travolta at a Grab-a-Granny night. I thought it might be in my mind, but on the second lap I might “ahem” have done a sub 51-second lap. Considering that previously a good lap around there for a standard-engined car is around 52 secs, that is a great time. I would have thought a sub 50 second was on, but the new (crap) brake fluid caused a soft pedal and I could not heel and toe. (Excuse no. 356, section D)