[TonyS]

I've been experimenting with taping off various gaps and seals to try and locate the cause of my wind noise, and discovered something very interesting about low speed engine/tyre/road noise.

In the engine bay, the tops of the wings from about halfway back (over the wheel arches) are sealed off, but at the start of the sealed area there is a large forward pointing hole. I stuffed an old rag in there to see if it helped with the wind noise - it did, but what astounded me was how much quieter the car was at low speeds. I took my wife out in the car and she immediately commented on how the car seemed quieter before we'd even got out of our road. The holes are in the area marked with the red circles in the photo below - it's a bit difficult to explain but if you stick your hand in there you'll see and feel them. The sealed off parts are the black rectangular areas above the red circles leading out of the top of the photo.

I can only assume that both engine and tyre/road noise are getting channelled into the sealed area at the top of the wings and then pushed back into the cabin. There are also large gaps at the back of the wings in front of the doors where I suspect this noise is ending up and being funnelled around the doors - see the latter part of this post for pics (http://www.f30post.com/forums/showpo...4&postcount=33) I intend to block these up to see what difference that makes as well. Note that diesel engined cars apparently have these gaps filled but petrol cars don't - maybe because diesels are noisier?

I shall be investigating this further when I have a bit more time and also something a bit better than an old rag to fill the hole with, but I'd be interested in seeing if anyone else finds it makes a difference.

[alex_chung]

That is interesting. Mines is not bad but I guess anything that helps would do.
Alex

[Dave_3]

Good work.

Road noise is slightly disappointing in the new F30/1/2s. I normally have the HK on so don't notice it too much.

I noticed the leading edge of the door on the F32 has a rubber edge to seal the forward gap, and the gutter rail also has some rubber infill.

If I could add additional refinement to keep tyre noise at bay, it would be welcome. Keep us posted.

D.

[F30AM]

Good work. I will be doing something similar when the weather improves.
I have no wind noise problems but would like to address the road noise with some sound proofing.

[TonyS]

Originally Posted by Dave_3

Good work.

Road noise is slightly disappointing in the new F30/1/2s. I normally have the HK on so don't notice it too much.

I noticed the leading edge of the door on the F32 has a rubber edge to seal the forward gap, and the gutter rail also has some rubber infill.

If I could add additional refinement to keep tyre noise at bay, it would be welcome. Keep us posted.

D.

Interesting that the F32 has the rubber door and gutter seals. Any chance you could post a photo or two, I'm trying to gather evidence to persuade my dealer that I have a genuine problem with wind noise (at the moment I'm being fobbed off with the "oh, they all do that sir" excuse). If BMW have modded the seals on the F32 then I may be able to use this.

[Dave_3]

Originally Posted by TonyS

Interesting that the F32 has the rubber door and gutter seals. Any chance you could post a photo or two, I'm trying to gather evidence to persuade my dealer that I have a genuine problem with wind noise (at the moment I'm being fobbed off with the "oh, they all do that sir" excuse). If BMW have modded the seals on the F32 then I may be able to use this.

Took a few quick shots tonight, will rescale on pc and upload tomorrow...

D.

[alex_chung]

I had a look last night on my F30 and could not see the gaps in the doors that were mentioned in previous posts but will check again this morning.
Alex

[TonyS]

Originally Posted by alex_chung

I had a look last night on my F30 and could not see the gaps in the doors that were mentioned in previous posts but will check again this morning.
Alex

Possible because you have a diesel - I've read that the gaps (which are in front of the doors, not in the doors themselves) are filled with a rubber (?) gasket of some sort on diesel models. I would guess that this is to reduce noise, diesel engines being noisier, which sort of lends weight to my theory that a lot of noise gets into the cabin through these gaps. If that's the case then it seems very penny-pinching of BMW not to fit the seals as standard.

[Dave_3]

Originally Posted by TonyS

Interesting that the F32 has the rubber door and gutter seals. Any chance you could post a photo or two .... .

Here is an image showing the leading edge seal on the door edge, and the gutter rail with a fat rubber gasket, top down view of the door shows the door seal and the gutter rubber.

I haven't noticed any wind noise right up to just over 130 Km/h, but I do have tyre roar entering the cabin - more than I expected.

D.

[TonyS]

Originally Posted by Dave_3

Here is an image showing the leading edge seal on the door edge, and the gutter rail with a fat rubber gasket, top down view of the door shows the door seal and the gutter rubber.

I haven't noticed any wind noise right up to just over 130 Km/h, but I do have tyre roar entering the cabin - more than I expected.

D.

Thanks for doing that. Very interesting that the F32 has that leading edge door seal. I can see how that might help to reduce noise by sealing off the large panel gap at the front of the door. Looking on realoem.com I can see that the F32 appears to have a number of extra seals around the door, e.g. there's also a "seam sealer" that runs round the bottom and back of the door that isn't present on the F30. Some of this may be due to the fact that the doors are longer of course.

Is that gutter rubber actually filling (at least partially) the gap between the roof and the window strip that runs round the top of the door, all the way from the front to the back? I can't really see the purpose of that, unless some of the wind noise is generated by the air being trapped between the roof and the window strip.

This has given me some other things to look at to try and reduce the wind noise on my car, so thanks again.

Your comment about tyre roar at high speed is very valid, I find the level higher than I'd expect for a car like this. There seems to be conflicting opinions on whether it's the run-flats, but I suspect a lot of it comes in via the boot, which seems to be very poorly insulated. I've got the BMW boot mat in mine, which does seem to make a bit of difference.

I've also found there are a couple of large holes in the underside of the rear parcel shelf which look like they would channel any noise from the boot straight into the car and then bounce it off the rear window at you (look inside the boot and up at the parcel shelf to see them). I've tried stuffing some cloth material in them which again seems to have helped a bit. I'm getting some acoustic foam tiles off a friend next week and will try some of them inside the boot to see if that quietens it down at all.

[dicky.hillary]

I would be eternally grateful if anyone comes up with methods of quietening the F31 down... my previous E92 had significantly less diesel clatter!

[teaston]

Originally Posted by dicky.hillary

I would be eternally grateful if anyone comes up with methods of quietening the F31 down... my previous E92 had significantly less diesel clatter!

Easy, change it for a 330d!

I can't believe how quiet my engine is compared to the E90 320d!

[dicky.hillary]

If money would have stretched to a 330D I would have took the plunge... however SWMBO put her foot down as we're getting married. The E92 320D was still far quieter than the F31 320D :-(. I used to own a the original Skoda Fabia VRS ( The one that used to annoy the Mini Drivers hehe ) That was very noisy until someone worked out that some Land Rover defender sound deadening could be fitted and posted a guide. After following that you could actually hear the turbo singing :-)

[Doc943]

Good work mate! I've been experimenting with plastic shims made out of tie wraps inserted at various points of the window seal, especially the top window seal to try and get the excessive wind noise down in my F30. I know the difference run flats and the Diesel engine makes but it's the wind noise invading the cabin space that really lets the car design down.

[Mungogrubb]

Originally Posted by TonyS

I've been experimenting with taping off various gaps and seals to try and locate the cause of my wind noise, and discovered something very interesting about low speed engine/tyre/road noise.

In the engine bay, the tops of the wings from about halfway back (over the wheel arches) are sealed off, but at the start of the sealed area there is a large forward pointing hole. I stuffed an old rag in there to see if it helped with the wind noise - it did, but what astounded me was how much quieter the car was at low speeds. I took my wife out in the car and she immediately commented on how the car seemed quieter before we'd even got out of our road. The holes are in the area marked with the red circles in the photo below - it's a bit difficult to explain but if you stick your hand in there you'll see and feel them. The sealed off parts are the black rectangular areas above the red circles leading out of the top of the photo.

I can only assume that both engine and tyre/road noise are getting channelled into the sealed area at the top of the wings and then pushed back into the cabin. There are also large gaps at the back of the wings in front of the doors where I suspect this noise is ending up and being funnelled around the doors - see the latter part of this post for pics (http://www.f30post.com/forums/showpo...4&postcount=33) I intend to block these up to see what difference that makes as well. Note that diesel engined cars apparently have these gaps filled but petrol cars don't - maybe because diesels are noisier?

I shall be investigating this further when I have a bit more time and also something a bit better than an old rag to fill the hole with, but I'd be interested in seeing if anyone else finds it makes a difference.

TonyS, you're a genius!

Whilst sceptical i gave it a go yesterday, all the same and i have to say there is a noticeable reduction in engine and road noise.

Even ran a decible check using an iPhone app, ran at the same speed on the same road twice, one with 'rags' one without. Not scientific, i know, but wanted to see if i just wanted it to be quieter.

The results were interesting-mid point of results with rags= 74Db
without 83Db!

[F30AM]

After I had my tyres filled with nitrogen and pressures set correctly, my ride is crap, the tyre roar seems louder. At least wind noise is low just as before. To add insult to injury, my Connected Drive is non-functional. Feel like driving the car off a cliff.

[TonyS]

Originally Posted by Mungogrubb

TonyS, you're a genius!

Whilst sceptical i gave it a go yesterday, all the same and i have to say there is a noticeable reduction in engine and road noise.

Even ran a decible check using an iPhone app, ran at the same speed on the same road twice, one with 'rags' one without. Not scientific, i know, but wanted to see if i just wanted it to be quieter.

The results were interesting-mid point of results with rags= 74Db
without 83Db!

That's great - I've been waiting for someone else to confirm what I found.

I've done a trip from West Sussex to Bristol and back today (first decent trip since discovering this), and the car really is quite a bit quieter. In particular, road surfaces like the concrete parts of the M25 are noticeably less noisy.

If you open the bonnet and look from the back of the front wings, through the vertical gap in front of the doors, you can actually see right through and out of the hole at the front, so it's got to be contributing to noise levels in the cabin from both the engine and front tyres. My next test is to fill the vertical gap with some backing rod which I'll get this week, and see if that helps any further.

[TonyS]

Originally Posted by F30AM

After I had my tyres filled with nitrogen and pressures set correctly, my ride is crap, the tyre roar seems louder. At least wind noise is low just as before. To add insult to injury, my Connected Drive is non-functional. Feel like driving the car off a cliff.

I've found the tyre pressures are quite critical, just a couple of psi seems to make a difference. I recently found my tyres were just a little low, so set them to recommended pressures, and the ride changed noticeably, and not for the better. I've reduced the pressures again and it's much more comfortable.

[F30AM]

Originally Posted by TonyS

I've found the tyre pressures are quite critical, just a couple of psi seems to make a difference. I recently found my tyres were just a little low, so set them to recommended pressures, and the ride changed noticeably, and not for the better. I've reduced the pressures again and it's much more comfortable.

Thanks.
Yes, that's what I will do tomorrow. If it is not one thing or another with these F30s that goes out of kilt.
Handling is great with these pressures and the car drives straight and true by being very stable.
Damn cars. Damn BMWs.

[ATM]

Swapped over from my go flat 17 inch Winters to the original 19 inch wheels with run flats. God the car feels awful now by comparison. I used to feel no bumps or bangs and the car rode on a cushion of air. Now it is the opposite. The amount of noise has definitely increased and the steering feels numb too. No way I am leaving them on for long. I need to decide what to do now. Either I use go flat tyres on the 19 wheels or switch to 18 with go flats. I'm even thinking about going back to 17 inch because the car felt so good with them on.

[pmgreenwood]

Originally Posted by ATM

Swapped over from my go flat 17 inch Winters to the original 19 inch wheels with run flats. God the car feels awful now by comparison. I used to feel no bumps or bangs and the car rode on a cushion of air. Now it is the opposite. The amount of noise has definitely increased and the steering feels numb too. No way I am leaving them on for long. I need to decide what to do now. Either I use go flat tyres on the 19 wheels or switch to 18 with go flats. I'm even thinking about going back to 17 inch because the car felt so good with them on.

I found my previous car an E91 was far nicer on winter 16,s than summer 17's. I find it tragic the way the UK tyre size market was been driven by looks or dry weather grip rather than overall performance. I will be buying a steel 16in winter set for my F31 in late October.

I would have bought an F31 luxury model rather than an SE but for the18in wheels. The effects on noise and ride above the 17's of the SE is the exact opposite to the word luxury. Marketing gone mad

[TonyS]

Just as an update to this thread, as well as packing the large hole in the front wings I've now also packed the huge vertical gaps at the back of the front wings (in front of the doors), and immediately noticed yet another improvement in low speed engine/tyre/road noise. Driving around the local roads, the car now sounds more like I would expect a £40k car to be.

At higher speeds the objectionable wind noise is also decreased, although the buffeting sound is still there.

Why BMW only fit a seal into that gap on diesel cars is beyond me. I also don't really understand the whole design of the doors, where the door seals are well inboard of the door edges, so that there is a large expanse of the door that is completely open to the airflow and dirt being thrown up - just look at how dirty the front sills get. I'm convinced that the doors not being sealed at their edges (plus the huge panel gaps) is also where a substantial part of the wind noise comes from, not helped by the front wings that channel air, venturi-like, onto the doors - hence my mods making such a difference.