My soundproofing and deadening project...

[BogdanM]

I really start to believe that the cars built in the US are built to different standard than the ones that are build in EU, at least for the EU market. The noise level in my car is perfectly ok, you can have a decent conversation even at 190km/h without raising your voice. Yes, there is some tyre noise on rough / abrasive asphalt (but on the other hand the Michelin Primacy 3 235/45R17 are tyres on the noisy side at 72dB vs 67-68) but other than that, no real engine noise, wind noise, traffic noise, etc.

Also, seen a lot of body panel fitment issues which seem to be happening for body styles built in the US. Maybe some cost cutting to keep the price low, also lower than EU?

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[Musclebadger]

You must have a lot of time to waste. Not sure why you would go through all of this??

I wouldn't call this a waste. Some people want a quiet interior. Better to do it right the first time then doing a crappy job the first time and being annoyed. It looks like a fun project.

 

[bahndrvr]

I did all of the trunk, rear seat area, and doors with 80mill Norinco, and then covered the trunk and doors with Closed cell foam, took my DB's from 98 at 80mph to 82 at 80 mph on same stretch of road. I have also done the very front of the footwells with Norinco and CCF as well, but will be removing seats to complete the task. The under seat area is REALLY open and I didn't realize till the other day, so definitely doing the entire floor. I'm also getting new tires on Tuesday which I suspect will put me under 80DB's at 80mph which is my goal, one huge benefit to the sound deadening was the increase in the sound of the stock Si Stereo and I didn't count on that I have put over 28k on my car in 9 months, to those saying it's a waste, drive in my shoes for a while, you'll realize how loud the cars are! I will be doing a full undercarriage coating soon as well as I belive that will help more than Anything I have done on the inside.

 

[BogdanM]

What have you used to measure the dB? 98 dB is huge, something is not right there, it’s like a pear of powerful headphones set to max, in which case you can’t hear anything else.

 

[bahndrvr]

What have you used to measure the dB? 98 dB is huge, something is not right there, it’s like a pear of powerful headphones set to max, in which case you can’t hear anything else.

I have Si, it comes with less sound deadening than most as I have verified against my neighbors EX-T, and touring has more than all others. I used phone app for testing, think i have some pics somewhere, and yes it was ridiculously loud, came from a BMW 335i and a 4Runner, my wifes Jeep Wrangler Unlimited was quieter than my car at 80mph when she had her hard top on, almost pissed me off enough to take it back...

Found a pic, only one I have is after the sound deadening was added to my car showing 81 db's.

 

[averagetrackdriver]

I did all of the trunk, rear seat area, and doors with 80mill Norinco, and then covered the trunk and doors with Closed cell foam, took my DB's from 98 at 80mph to 82 at 80 mph on same stretch of road. I have also done the very front of the footwells with Norinco and CCF as well, but will be removing seats to complete the task. The under seat area is REALLY open and I didn't realize till the other day, so definitely doing the entire floor. I'm also getting new tires on Tuesday which I suspect will put me under 80DB's at 80mph which is my goal, one huge benefit to the sound deadening was the increase in the sound of the stock Si Stereo and I didn't count on that I have put over 28k on my car in 9 months, to those saying it's a waste, drive in my shoes for a while, you'll realize how loud the cars are! I will be doing a full undercarriage coating soon as well as I belive that will help more than Anything I have done on the inside.

That's really good news about the significant drop in db's with the Norinco and CCF. As for the undercarriage coating, what are you thinking of using? I'm wondering how much additional weight will you add with the Norinco, CCF, and the coating?

 

[bahndrvr]

That's really good news about the significant drop in db's with the Norinco and CCF. As for the undercarriage coating, what are you thinking of using? I'm wondering how much additional weight will you add with the Norinco, CCF, and the coating?

Maybe 20lbs the CCF weighs nothing, the butyl on the other hand... I can look back and see actually but it’s well worth it and my rims I’m refinishing are 12lbs lighter each rim and I went with 21.3 lb tires compared to the almost 27lb tires from stock! Next week loosing 60+ lbs of un-sprung weight which is around 10-1!

 

[Spacesloth]

I’ve done a little myself with the doors. MLV over the door opening and denim insulation on the door panel itself.

 

[DiamondPuma]

It seems we get a little better insulation in china:

My car became a lot quieter after spraying the bottom with chassis armour.

Oh wow, you did your interior too? Didn't think anyone would xD

 

[DiamondPuma]

You must have a lot of time to waste. Not sure why you would go through all of this??

I'll do almost anything for better audio...

 

[DiamondPuma]

Maybe 20lbs the CCF weighs nothing, the butyl on the other hand... I can look back and see actually but it’s well worth it and my rims I’m refinishing are 12lbs lighter each rim and I went with 21.3 lb tires compared to the almost 27lb tires from stock! Next week loosing 60+ lbs of un-sprung weight which is around 10-1!

Probably added 60lbs in total to my ride, may try to drop some in rims and tires to get back to the equilibrium or a little past that. What're the best places to shed weight?

 

[DiamondPuma]

I’ve done a little myself with the doors. MLV over the door opening and denim insulation on the door panel itself.

Nice!! Looking good!

 

[CivicChina]

Oh wow, you did your interior too? Didn't think anyone would xD

no, the picture is from the local civic mod garage. I just sprayed the bottom and i think it is more than enough, my little tires help reduce the noise, and we have veeeeery smooth roads.

 

[DiamondPuma]

no, the picture is from the local civic mod garage. I just sprayed the bottom and i think it is more than enough, my little tires help reduce the noise, and we have veeeeery smooth roads.

*sigh smooth roads...

 

[n9yty]

I'm mostly going deaf, LoL, or so it seems. But at any rate, I don't find it bad. What I do find annoying, and it doesn't seem to be there all the time, but it is some noise coming through what sounds like the pillar between front and back doors, or that the doors aren't sealing well, and so when passing cars/etc I get noise there, which otherwise I don't hear much of anything. Strange... But hey, definitely, PROPS to OP for this, most impressive.