NightFox
Member Since: 02 Apr 2005
Location: Bedfordshire
Posts: 125
|
Here's something to try - when you're doing about 60-70 mph, with the rest of the windows up, put just the rear passenger side window all the way down.
I'm not going to tell you what happens or that would spoil the surprise - don't worry, it wont cause any damage though (at least not to the car).
Go on, try it and post your experiences here!
|
28th May 2005 11:15 pm |
|
|
Slimer
Site Moderator
Member Since: 06 Jan 2005
Location: Last Exit to Nowhere
Posts: 16295
|
Haven't tried it but I seem to remember a possible 'issue' that may occur in this senario in the handbook somewhere The End
|
29th May 2005 12:17 am |
|
|
marc
Member Since: 21 Feb 2005
Location: Nottingham
Posts: 169
|
Isn't this something to do with a drumming sound???
Quite loud from what I remember in previous cars.
Marc Disco 3 now gone!!
Discovery 3 S spec 2.7 V6 Diesel.
Previous Car to D3: Seat Leon Cupra R with a nice 280 bhp...... Sad to see it go
|
29th May 2005 8:42 pm |
|
|
simon
Member Since: 11 Jan 2005
Location: Shropshire
Posts: 18296
|
This happened on the Audi I had last and also the Bimmer too.
You need to crack the front window slightly to get rid of the buffeting.
-s
|
30th May 2005 9:42 pm |
|
|
Keith Walshe
Member Since: 28 Feb 2005
Location: Sydney
Posts: 53
|
It has to do with the Bernoulli effect- fast flowing liquid / gas caused a pressure reduction and tries to suck air out of the car but if there is only the normal A/C on it cannot susck the air out fast enough and this sets up standing (pressure) waves in the air which you feel and hear. Hence opeing a front window just a crack relieves the situation.
Disco2's do it as well.
I used to have one of these in the bottom of my racing dingy - little more than a hole in the bottom of the boat but once you got moving it sucked the dingy dry.
|
31st May 2005 7:36 am |
|
|
NightFox
Member Since: 02 Apr 2005
Location: Bedfordshire
Posts: 125
|
For any readers who haven’t actually got D3s, you can simulate this effect by getting a tennis ball, cutting it in half, placing one half over each ear and pumping them vigorously at the rate of approx 5 pumps/second until you either:
a) Rupture your ear drums
b) Experience a straw-coloured discharge from your ears
c) Pass out
d) All of the above
I hereby challenge anyone to drive for more than 10 seconds at 70mph with just their rear passenger-side window open.
Pardon?
|
31st May 2005 9:36 am |
|
|
BN
Member Since: 18 Mar 2005
Location: Here
Posts: 6463
|
Well the weights underneath are for vibration, so perhaps they should have placed ear defenders inside for the sonic boom
|
31st May 2005 9:56 am |
|
|
ducati
Member Since: 06 May 2005
Location: Ohio, USA
Posts: 180
|
I spoke with a fella from Land Rover a few weeks ago and this was one thing he mentioned he was very displaeased about with the LR3/D3. He claimed the flat sides intensify the effect.
Although this happened to a certain extent on my D2, it was nowhere near as ear-rupturing as on the D3. '05 LR3 HSE
Departed: '62 Series IIA, '02 Freelander, '03 Disco
|
31st May 2005 2:26 pm |
|
|
Slimer
Site Moderator
Member Since: 06 Jan 2005
Location: Last Exit to Nowhere
Posts: 16295
|
Tried it today, yup it's noisy!
Bit surprised about your fella from LR being very displeased about it, it's hardly a major design flaw, if anything it shows just how air-tight the car is.
It's no trouble to wind the front window down a tad or not put the back one all the way down The End
|
31st May 2005 9:49 pm |
|
|
Nickhearne
Member Since: 28 May 2005
Location: Ibstone Bucks
Posts: 996
|
I have to say I do not think I have had a car that dose not do this!
I would not call it a fault!
Nick D5 HSE Waitona Grey 2015
Range Rover Sport Estate 2.0 P400e Hse Dynamic Black
D4 HSE Santorini Black
Almond Arabica hide & Walnut trim Now sold
Discovery 3 TDV6 SE
Zambezi Silver Ebony leather Now sold
|
1st Jun 2005 8:36 am |
|
|
BN
Member Since: 18 Mar 2005
Location: Here
Posts: 6463
|
Nick, a very good point. However, you don't get the booming on a double deck bus with the rear open in London
Seriously though, it is quite normal I think with most cars, the D3 is just a bit bigger, a bit faster and a bit more pronounced maybe.
|
1st Jun 2005 9:41 am |
|
|
ducati
Member Since: 06 May 2005
Location: Ohio, USA
Posts: 180
|
His point was the *design* of the body influenced this in a negative manner, and he's a form follows function kinda guy... '05 LR3 HSE
Departed: '62 Series IIA, '02 Freelander, '03 Disco
|
2nd Jun 2005 7:27 pm |
|
|
Nickhearne
Member Since: 28 May 2005
Location: Ibstone Bucks
Posts: 996
|
Tried this last night at only about 50mph, this would have to be the loudest car I have had!
Chickened out to go any faster!
Nick D5 HSE Waitona Grey 2015
Range Rover Sport Estate 2.0 P400e Hse Dynamic Black
D4 HSE Santorini Black
Almond Arabica hide & Walnut trim Now sold
Discovery 3 TDV6 SE
Zambezi Silver Ebony leather Now sold
|
3rd Jun 2005 7:22 am |
|
|
nobbyclark
Member Since: 03 May 2005
Location: Perth, Scotland
Posts: 1268
|
Happens in my Tdi 300 too and my Cooper S with the sunroof open.
|
7th Jun 2005 2:52 pm |
|
|
Gareth
Site Moderator
Member Since: 07 Dec 2004
Location: Bramhall
Posts: 26774
|
At great risk of personal injury, I today decided to once and for all try to find out the extent of this so called audible phenomenon.
I set off from the services on the M56 with the left rear window fully down. All the other windows were closed. As I passed 40mph, the was a distinct whumph -whumph - whumph noise developing, it was not however excessive at this stage of the experiment. I continued to accelerate, and by 55mph it was starting to get very loud. At 60 mph I considered aborting the test run, but I gritted my teeth and made a final push to see whether in fact the noise would become so loud, as to become a danger local residents -who may have mistaken it for a sonic boom.
As I pushed on, with fingernails firmly embedded in the steering wheel, expecting the worse, I was mildly surprised to find that at 80 mph the sound started to recede, and by 100mph it was in fact perfectly smooth.
So I can conclude, that the noise experienced by many partakers of this forum, is in fact a form of sonic resonance caused by unstable airflow around the side of the car. This is, in my opinion, not a problem, as it is obviously only a temporary senstation as the car passes through the sound barrier, on its way to its normal cruising speed.
|
7th Jun 2005 4:27 pm |
|
|