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Sound isolation

74K views 65 replies 32 participants last post by  etusch 
#1 · (Edited by Moderator)
Hi to all.

I am Rasmus, a more or less happy Civic owner from Estonia.

I bought my car a week before christmas and at first I was pretty happy with things. That probably has something to do with the fact that for the week before that I was forced to drive a rental Daewoo (trust me, its hard to come up with a car worse than that).

The car I had before was a Mitsubishi Sigma, which can more or less be counted as an exec car and has all the comforts: powered everything, auto box, silky smooth ride and a quiet, comfortable interior. So it wasn't long since the first and blind love of the Civic was overshadowed by the amount of noise I would have to put up with while driving. I mean it's OK in the city at low speeds, but having to cover longer distances at high speeds - the road noise just does my head in. Also, driving on rougher tarmac or bad roads (there are plenty of them here) made too much noise, mainly because the dampers used on the Civic are skanky but also because the wheelarches don't have much isolation on them.

So I decided to take some steps against that.

1. Went down to the local car audio dealership and bought some materials: a roll of cotton cloth (its not actually cotton), 4 sheets of 4mm bitumen isolation and 4 sheets of 2mm bitumen isolation. They all have one side in adhesive so it's quite easy to use them, no worries with making them stick. The bitumen sheets are 50cm by 50cm and all add up to about 15kg.
Since the weather here is even worse than it is in England I obviously had to do this inside. The installation instructions for the bitumen mats states that the temperature must be at least 15C for the thinner one and preferably higher for the thicker one, so an industrial blower will be needed unless you do the work in spain.


2. For starters I decided to work the doors. Mainly because I know the panels will come off nice and secondly because that's where the speakers are. And soundproof doors make a hell of a difference in the sound quality. The doorpanels come off after unscrewing three screws and pulling to make the poppers pop. Again, temperature works in your favour with the poppers, if its cold then they have the tendancy to break. Its OK though, they are not too difficult to find and cost little too - just as long as you don't go to find them at your local Honda dealer (where everything apart from the cars tends to be a ripoff). Afer that you will have to unplug the wires for power windows and unhook the cables for doorlocks and the panel is free. Unscrew and remove the speaker, as this area will definately need isolation and the hole is good access to the outer inside of the door.

And here is what is revealed:

Vehicle door Vehicle Car Automotive exterior Auto part


This is all that Honda bothered to install as soundproofing:

Auto part Rim Vehicle Car Wheel


And this is the inside of the door panel. Not very impressive, is it?

Technology Automotive exterior Auto part Vehicle


After that you will need to peel the plastic isolation. Be careful here, this tends to get messy as the black glue used to keep this tight makes a mess. You won't need to peel the whole thing off, just make enough space so you can put both of your hands through the door.


3. Clean the inside of the door from any water or dirt. The metal will need to be fairly clean to make sure the isolation sticks and hangs on. Brake cleaner does the job quite well, but be careful, as the sides of the door are sharpish and you can slice your veins pretty easily.


4. Cut out appropriate pieces of bitumen and try them out before heating them up and removing the adhesive. I mainly used 2mm bitumen as it is lighter, but right under the speaker and in the lower part of the door I used both 4mm and 2mm bitumen to ensure better sound quality and minimize vibrations. You can, ofcourse, use 4mm throughout but you don't want to make the doors too heavy - it will wear out the hinges eventually meaning the doors will be harder to close. Also, according to specialists there isn't really a need to cover 100% of the door, they say that 70% of the soundproofing is done by covering 40% of the surface. Heating them up with the blower means the glue is in a better state and you can also mold the bitumen according to the surface - which is neccesary in order to make it stick.

Metal


The results were something like that:

Automotive exterior Auto part Trunk Hood Vehicle


Here is that same speakerhole afterwards:

Rim


5. Use the cotton cloth or some other soft isolation materials to cover the plastic areas on the inside of the door panel. This will stop higher frequency noises and minimize squeaks that occur when plastic scratches against metal. Keep in mind you don't want to cover up any popper or screw holes. So the inside of the door panel should look like this:



Auto part Vehicle



6. Close the plastic covering, reinstall the speaker, attach the cables, plug in the wires and place the door panel back on. Make sure everything is in place, push the poppers back in and tighten the screws.


I haven't had the means to measure how much the soundproofing changed in decibels, but the doors definately make a nicer sound when closed (there isnt any metallic noise any more) and surprisingly the car feels a lot firmer, smoother and quieter on bad roads. Bumps and potholes don't make as much noise, but mostly - the quality sound is improved greatly. It just sounds cleaner, more powerful and nicer in every way.

The road noise isn't completely solved though - the front and rear wheelarches need same work. I will get to that sometime soon hopefully. Pics and story to follow.
 
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#4 ·
wow great i look forward to more tips, i wish you lived here as iwould be calling on your services lol
 
#5 · (Edited by Moderator)
Vol2

After doing the doors I still had two sheets of 4mm bitumen and one sheet of 2mm bitumen left and majority of the 1x2m cotton mat was unused, so I decided to continue soundproofing the car from the rear. Seeing many cheaper japanese cars trunks and rear wheel arches I knew that adding soundproofing there will greatly reduce road noise and also create a better surrounding for a subwoofer in the future.

So I started with removing the rear trim.

1. Remove the wheel repair kit (right) and the jack (left).

2. Remove the top (window) shelf.

3. Push the rear seats forward and remove the trim between the seats and the trunk (attached by velcro on the seats and with clips on the trunk side).

4. Use a 10mm wrench to unscrew the bolts two bolts that are revealed next to the hinges of the trunk floor lid.

5. Lift up the trunk floor lid and you will see two caps in each corner of the floor. Remove these with a screwdriver and unscrew the 10mm bolts revealed.

6. Carefully pull off the rear plastic panel around the trunk lock hook, then pulling upwards remove the rear panel.

7. On the right side inside the tyre repair kit pocket you will see two clips. Push these and pull out the pocket which is to the left of them.

8. Right next to the rear doors, on the floor where the seatbelt goes are small panels covering them. Remove them on both sides.

9. Also remove the rear kickplates (the doorsill part).

10. Grab hold of one of the side panels (doesn't matter which one you choose
first), preferably from the rear (the tyre repair or jack pockets are good places to pull from) and carefully pull. There are four poppers holding the panels (three from the top and one right next to the seatbelt hook on the floor). Also be aware that once you get the poppers released you will need to undo the light cable on the right side and the 12V socket cable on the left side. It will seem as though it is stuck but this is merely because the hooks which hold the rear seat in upright position don't want to go through the trim too easily, so you will probably have to give it a little yank.

11. Remove the floor mat.

This is what is revealed:

Auto part Automotive exterior Vehicle


Auto part Automotive exterior Engine Vehicle Hood


Trunk Vehicle Auto part Car Engine



As you can see, Honda have added a little soundpoofing here, but its not quite adequate still.

As I was unsure of how close the trim and metal were at some places I took great care in selecting the places where I added thicker bitumen and where I had to limit myself to thinner one. Obviously, having the whole area covered will have slightly greater effects but like I said earlier: its not matter of quantity but its a matter of where you add the proofing. So firstly it would make sense to make sure the wheel arches are covered, then move on to other areas. I also added some around the damper mountings as this reduced the sounds that come from rough roads and of course on the floor of the trunk as this space made a horrible noise when knocked on.

After I was done, this is what it looked like.

Tire Automotive exterior Auto part Automotive wheel system Wheel


Auto part Engine Machine


Auto part Car Vehicle Bumper Automotive exterior



Job wasn't too well done on my behalf, as I was kind of in a hurry, so I didn't have too much time to bother with measuring and cutting the pieces exact, but they all got attached tight and more or less in the right places.

Likewise here as with the doors, I added extra cotton (somebody please correct me on this, its not exactly cotton, is it?) to the insides of the trim panels. Here's what they looked like before and after:

Bumper Automotive exterior Auto part Fender Metal


Vehicle Automotive exterior Car Hood Automotive window part



Once I was done with that you had to reattach all the removed trim in reverse order, making sure all the poppers were in place and wires attached.
Now the car sounds a lot quieter in the back, there is much less road noise there and also I don't hear the rear dampers as often as I did before. But then again, there is still some road noise coming in from the front wheel arches and at high speeds the roof acts like a diffuser to magnify the wind noise, so in the near future I will need to do something about these problems.
So far alltogether I have used 1 square metre of 4mm and 1square metre of 2mm bitumen totalling about 10kg plus 2square metres of cotton, another kilo of weight.

Total spent is just under £40, but I have no clue of what these materials might cost elsewhere.

To do the four doors took about 4 hours, the trunk took about 2,5 hours.
So overall this all is relatively cheap and not much hassle, but the effects are definitely worth it!

To be continued...
 
#6 ·
when i have mine back i shall definatley be doing this, maybe the boot inside the trim as well could be done
 
#7 ·
Spent 6 hours on Sat. fitting Infinity 6510cs upgrade. I also took time to sound deadening the doors. A well worth upgrade,after reading this thread I think I may do the boot next. One tip I have learnt is that you do not have to cover the whole area. Thanks for the info and photos
 
#9 · (Edited)
Nice work Rasmus !
I also did some parts using roof-fix bitumen (except the doors)
For the front wheel arches, you can remove the plastic inner arch and add some bitumen to the bodywork panels, also stuff some isolation in the holes. It is a bit dificult on the right side, since there is the water tank located.
For the rear arches I sprayed some extra layer of bitumen/ruber compount, when the car was new (even before I drove it).
Now I plan to glue some carpet material in the rear arches.
Keep up the good work!

I had a lot of Honda's, despite what you see here, the Civic had the most standard isolation allready in place of all of them...
 
#10 · (Edited)
Vol3 : floor and front wheel arches.

So I had run out of isolation materials and went to a local car audio dealer, where I found a new range of excellent isolation materials. I bought two 60x90cm sheets of the thinnest isolation mats, which cost me about 30 euros. Still had some cotton left, so didn't have to buy any more of that.

1. Remove all of the floor mats. Put the rear seats into upright position. Remove the floor hooks (on the pic below). Philips screwdriver needed.

Trunk Vehicle Car Vehicle door Automotive exterior


2. Remove the all of the kickplates.

3. Remove the B pillar trim.

4. Remove the front seats (14mm wrench needed). There are four bolts at each corner which can be undone quite easily. After that carefully unplug all the wires underneath the seats.

Land vehicle Vehicle Car Vehicle door Automotive exterior


5. Remove the outer side panels in the footwell. Both attached with 2 poppers.

6. Remove the footrest cover (2 poppers) and unscrew the metal part (two 8mm nuts, but need a longer, cylindrical wrench here).

After that, you can lift up the carpet enough to add some soundproofing materials. As there is some already there, I did the areas which were left bare in the factory. Of course, the more the merrier, especially on the wheel arches, but you have to remember, that all the trim and carpets need to be refitted, so you can't add too much.

The most annoying part is doing the front footwells, you have to try to reach as far up as possible but you can't completely remove the carpets or the existing soft sound isolation material there. The front wall is where most of the noise comes from - both engine and road noise from front wheelarches. The rights passenger side is ok to access, but on the drivers side you also have the pedals - and removing those just isn't worth it.

Afterwards you are done (use up all the material you have, especially on the front wall although it is difficult to put anything under the carpet there), just put everything back where it belonged and make sure you don't break any poppers - I busted two attaching the side trim in the footwell. It took me alone 3,5 hours altogether to do the floor and footwells.

Automotive exterior Vehicle Car Bumper Auto part


Automotive exterior Vehicle door Floor Bumper Auto part


The results - well, I used some newer type of isolation material called "vibroplast", which is a special, light and easily moldable compound that has a folium cover - they claim it to be very effective in a wide range of temperatures. Costs a little more than plain bitumen, but its so much nicer to work with (doesn't really need heating and the glue is much stronger).
Obviously there is lesser road noise, but I had the opportunity to drive a Lexus GS straight after that, and to be honest, that car is still way quieter and more refined in every aspect (the trim doesn't make a sound on bad roads). I know, the price is 3 times higher too, but I admire the work they do at Lexus!

So as far as making a Civic quieter, I have succeeded, but I am not completely satisfied with the results.

To be picky, there are two more things that ought to be done - the roof and some under the bonnet. I will see over the next few days whether or not I can actually be bothered to do them (the roof seems a lot of work).
I have some ideas about the front wheelarches, so hopefully soon this guide will be complete.

But what I do want to do sometime sooner or later is measure the noise level inside my car. I would bet for 4 decibels less, but who knows?
 
#11 ·
Good work Rasmus. I'm glad someone took the time to take photo's and do a write up, I just haven't got the time/patience/inclination!

You'll find the bonnet really difficult to do, I doubt you'll get the bonnet liner off without breaking the clips, and they're an extortionate price to replace. With a bit of tinkering and some long reach needle nose pliers, you might just be able to close the clips so that they pop out.... Good luck trying.

From experience (did 2 previous cars) soundproofing the bonnet has a beneficial effect, but not quite how you'd imagine. Most of the sound from the engine is transmitted through the bulkhead, so isn't effected by soundproofing the bonnet but some high frequency noise still passes through the windscreen area, which is cut dramatically. However, it will be noticeably quieter outside the car at idle. What you're likely to notice is that there's less wind noise generated through the bonnet as it will be more rigid. (It'll be less prone to huge dents when you hit a fly/stone/feather at speed too!)

You could also try to soundproof the bulkhead, if you can get to it. This will cut noise intrusion from the engine bay into the car interior.

Overall, it adds up to a quieter car. As you've seen, it's not expensive and requires minimal technical expertise. Well done BTW for getting the door cards off with all the clips still attached! That's got to be one of the most stressful car related moments of recent years for me! I must be less patient or more heavy handed than you, because I broke quite a few clips!

Well done again!

Damian
 
#12 ·
Thanks Damian, as I said, I am probably not finished with this car yet, so I will hopefully continue this thread soon.
About the bonnet - the results you mentioned are pretty much what I am looking for. Doing the roof should have the same effect of cutting out wind noise and making it firmer - so when bigger rain drops hit the roof it doesn't sound like a drum.
I am also thinking about doing the wheel arches from the outside (not from the interior but from the wheel side). There are some special materials for this, I am still researching this tho.
So in the end, when I am done, this car should ride smooth and quiet, but the engine should still be hear when you push it. Engines make nice noise, whereas bad roads just give me a headache.

Tips for anyone who is planning to improve the soundproofing:
1. Spare enough time. Its not reccomended to remove the trim too many times, as the poppers wear out and since the materials used in a Civic are mainly plastic, they have the tendancy to break. I don't want to know what new door cards might cost.
2. Make sure you have enough of materials. "Too much is never enough" you will always find a spot here or there when you've run out. Adding double layer in most crucial parts (under the speaker or on the wheelarches) will have great effects.
3. Make sure you have some (5 should be enough) extra poppers - cause if you do brake them its best to be able to assemble the car in one go.
4. For the most optimum results, I would start off with doing the front doors and front wheel arches. The trim is easy to remove and you can actually do the footwells without having to remove the seats, so all you will need is a phillips screwdriver and isolation materials (providing you use the "virboplast" i mentioned earlier). 3 sheets (60x90cm) of vibroplast and some cotton will do thejob quite easy.
4. Make sure you don't add too much materials - as the trim might not fit too well later in tighter spaces. And make sure you don't cover up the popper holes!
5. Use good quality materials. There is no point in saving a tenner here. The virboplast I used in vol3 is far greater to work with and has all the better characteristics, plus its as light as the 2mm bitumen. I would, in some crucial places use thicker vibroplast or bimast (yet another compound but thicker and heavier), but if I was to start doing this all over, I would probably not use regular bitumen at all.
6. To understand the results better, do all of the work over the weekend and do not drive the car before you are finished. I did mine bit by bit so its hard to appreciate the hard work :)
 
#13 ·
Rasmus,
Well done on a most educational thread. You reckon about a 4db reduction in noise, that's more than 50%, right ?
May I ask a couple of general questions ?
Are the door poppers generally available or do I need the dealers ?
Are there any safety considerations regarding airbags when removing the front seats ?
Thankyou.
 
#14 ·
Well, 4db is what I think it ought to be. It should be about the same difference as having the balance of the speakers completely faded to one side. The overall sound level inside the standard car should be about 74db at 110km/h, but I will try to get it tested if I have a chance.
About the poppers, I do not know where you could get them from in other countries, but in Estonia there are some shops that sell all kinds of parts for cars, that's where I've found them so far. And the difference in price, compared to the original Honda poppers is about 10 times (Honda originals cost about 2-3 euros per piece).
While removing the seats, after you have unscrewed all the nuts just tilt the seat backwards and unplug the wires underneath it (those are for heated seats - if you have them). I don't think there is anything to do with airbags there. But like I said - you don't neccessarily have to remove them, it makes the floor under the carpets more accessible so you can lift it up more. But if I was to do it again, I wouldnt remove the seats again.
 
#17 ·
Vibroplast

How much Vibroplast would be needed to do the sound isolation as you did Rasmus?

Here in Finland they sell packages including 6 pieces of 450 x 300 mm. They cost 39 € for one package.

http://www.powerset.fi/autohifi/tarvikkeet-a/vibroplast.htm

I have to find someone to do the job for me, because I am totally bad dealing with cars. I am just happy to be able to check the oil and fuel up the car :)

Is there something else to do to isolate the sound even more, or is this method enough to remove most of the road noise?
 
#18 ·
How much Vibroplast would be needed to do the sound isolation as you did Rasmus?

Here in Finland they sell packages including 6 pieces of 450 x 300 mm. They cost 39 € for one package.

http://www.powerset.fi/autohifi/tarvikkeet-a/vibroplast.htm

I have to find someone to do the job for me, because I am totally bad dealing with cars. I am just happy to be able to check the oil and fuel up the car :)

Is there something else to do to isolate the sound even more, or is this method enough to remove most of the road noise?
To do the whole car (front and rear wheel arches, all doors) you will need 4 big (60x90cm) sheets of vibroplast. And yes, I used the same material they sell in Finland, but here they sell it in two options: package of 6 sheets or big sheets. Plus I would reccomend you also buy some BiMast (thicker stuff) for the critical areas. It wouldnt hurt to do all the floor and the front wall as well.
 
#20 ·
I wouldn't use too much of bimast. Vibroplast itself is very good but its much thinner and lighter.
If I was to do my Civic over again, this is what I would use:
1 sheet of vibroplast for each door
1 sheet of bimast for each wheelarch
1 sheet of vibroplast for the trunk
1 sheet (I suppose) of vibroplast for the roof
So total of a package of bimast and 6 big sheets (or 4 packages) of vibroplast + some soft isolation material should be enough.
You can always go nuts and do your whole car - like these guys ( http://www.kalliojarvi.net/ibiza/vaimennus/ ), but in the end the more isolation the more weight and like I said, you will never make this car into a luxury vehicle, so in my view there is no point in doing that much. And remember, that reducing sound means reducing vibrations, so its good to use different materials in layers.
For example, road/tyre noise is a lower frequency, so it can be reduced by adding thick, elastic substances on metallic areas (vibroplast) to stop it flooding around the car, but there are also higher frequency noises which are better suppressed by foams, cloth etc.
So remember, its not a matter of quantity, but a matter of smart placement.
 
#21 ·
Awesome, informative thread Rasmus[smilie=ebil-thumbu:. All I need now is the car and the materials!

Anyone sourced the materials in the UK yet? Googled "vibroplast" and got this tread and non-English language sites. Is there a UK alternative?
[/COLOR]
 
#23 · (Edited)
Right. As most Civic owners I wasn't too happy with the sound of the original speakers, so after giving it some thought I deciced to change the front speakers.
I took time choosing the speakers - I didn't want to spend a fortune on them but yet they needed to be good quality, with a wide band and good output characteristics - to ensure nice, clean sound.
Since my car is a 1.8 Comfort - it only has 4 speakers (no tweeters in front), so I decided to go for coaxial speakers.
The speakers I bought in the end were MDS (a swedish company), model F216:
RMS rating: 100w, Max 200w, frequency 28 - 25000Hz, sensitivity 93,9dB.
Here is the best part - the price was only 38 euros for the pair (12 off).
Comparing them to the original speaker, we can see how pathetic the originals are:



As a tip from Pottsy's thread I also bought a set of Astra speaker adapters for 12 euros.
Then I removed the front door panels again, removed the old speaker, attached the rings, brazed the wiring and screwed the speaker onto the rings.

The thing that annoyed me the most was that the wiring - how on earth do you tell which is + or -??? If you wire the speakers up wrong, there isnt much use of installing better speakers - it will sound crap. So i had to try them out one way and the other until one wise guy came around and helped me out. I got so confused for a while, I'd probably still be in the garage if I was alone!:mad:
Anyhow, the speakers are, ofcourse, a lot better than the original ones. Before I didn't dare turn the volume past 25 - it sounded as if the speakers were about to rip. Now I can go all the way up to 35, it sounds loud and clear. The stereo now outputs sounds I never heard with the original speakers.
However, as clear and loud it may be this setup is still weak - there isn't enough bass. So I am going to have to install a subwoofer sometime soon.
I was thinking of going for an acitive woofer but a woofer needs RCA signal - so I'm going to have to remove the rear door panel to get the signal. Which means I really should install some new speakers there as well.
Meanwhile, the cops have decided to stop my drivinglicense for 2 months - so I guess there is no point in installing all this now if I can't use it :(
 
#24 ·
The thing that annoyed me the most was that the wiring - how on earth do you tell which is + or -??? If you wire the speakers up wrong, there isnt much use of installing better speakers - it will sound crap.
The easiest and most low-tech way to check, is using a 9Volt battery (you know the type with the contacts both at the same end). Hold the old speaker in one hand (with your hand on the cone) and touch the battery contacts onto the electrical contacts of the speaker. When the Cone Moves out, the contact with the battery positive on is the positive contact of the speaker. If you mark one of the wires and the contact it came off, you now know what wire does what.
 
#25 ·
Sound isolation didn't help :-(

Now I have also done the sound isolation to my car.

It was done by a car stereo installer here in Finland.

He used about 4 packages of Vibroplast, about 2 square metres of 4 mm bitum isolation and about the same with 2 mm bitum, other than Vibroplast.

On the doors he used Noxydol on the thicker parts.

He said that the weight of the car increased with about 50 kilos.

He isolated all the doors, floor and the whole trunk.

I have to say that it didn't help almost nothing to the road noise :(

So is there anything else to do?

Only thing left to do is to change the tires?

Now I have Michelin Primacy, 225/45/17.

Can I change to 205/50(55)17 or should I change the wheels too and buy 16 inch wheels+tires instead?

What brand of tires could be the most silent ones and would still be good tires?

Or is there something wrong with the sound isolation of my car? Shouldn't the sound isolation made make some kind of difference in the road noise?
 
#31 ·
What brand of tires could be the most silent ones and would still be good tires?
I too have Michelin tyres, and they are very noisy. I've been thinking about changing them. But I think I'll wait until next year. I think I can cope with it.
But these are some tyres that at least are promoted as comfort and quiet tyres: Durun A-one, Durun sport one, Roadstone N 3000 and Roadstone N 7000.
Note I haven't tried any of them. So I cannot tell you if they are any good on our Civics'. They cost €170-€230 per tyre
 
#26 ·
Did he do the front footwells and rear wheelarches?
Doing the doors, trunk and only floor will not eliminate road noise too well, most of the noise comes from the tyres - so the area around them needs to be covered.
But then again, doing a complete sound isolation on the car will make it quieter, but you will still be able to hear some road noise.
About tyres, I have no suggestions. My car has the standard 205/65r16 bridgestone's and according to some latest test they were the best all arounder (best top score).
 
#27 ·
I am not sure if he did the front footwells. I think he did the rear wheel arches.

The total time he spend on the isolation was almost 9 hours.

I will ask him about the front footwells.

I think the only way to get the tire noise down is to buy more silent tires. I think I need to go down to the size of tires that you Rasmus have...::rolleyes:
 
#28 ·
Well, 50kgs is a hell of a lot of isolation materials, so he must have put them in useless places if there is still a lot of road noise going in your car.
Or maybe you are trying the car on rough tarmac? We have a lot of rough surfaced roads here in Estonia and even the quietest of cars produce hearible noise on these roads.
16" are more comfortable and probably a bit quieter, but changing all the wheels and tyres is quite a price, I suggest you try driving a Civic similar to your own and see if there is a difference in road noise before you start changing tyres.
 
#29 ·
Yes the roads here in Finland has alot of rough tarmac, and the car is more quiet on better tarmac.

I will see if I go and testdrive a Civic at a car dealer to see if there is any difference in road noise.

I just wish I would have the money to buy a Lexus. I test drive a RX300 a few years ago and it was so quiet :) But then the price difference is another too compared to the Civic :rolleyes:
 
#30 ·
Yes the roads here in Finland has alot of rough tarmac, and the car is more quiet on better tarmac.

I will see if I go and testdrive a Civic at a car dealer to see if there is any difference in road noise.

I just wish I would have the money to buy a Lexus. I test drive a RX300 a few years ago and it was so quiet :) But then the price difference is another too compared to the Civic :rolleyes:
When you check that they did the wheel arches, make sure that the suspension mount turret tops have also been done. A lot of sound can be transfered through the top mounts and into the chassis. (Both front and rear need covering. Two layers would be best at these points).
 
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