bmwe21.net forums

please bear with me about this post, i dont want to be made fun of because im getting old now.

My e21 is primarily a road car, and although I have told the exhaust shop to fit the quiet as possible exhaust (its not loud on tick over), you still get far too much road noise / rumble, you hear little stones being flicked up into the arch etc,

Has anyone here ever improved the sound deadening / suppression of their e21s at all?

If so what stuff do i use and where do i get it. when i get it where do i stick it and anything else you can tell me to help?

My work for 10 years was car audio (insulating, custom installs,...)

this is a top shit option :

http://www.ebay.co.uk/itm/DMR-22505-Who ... 1e888aaaae

with 1 roll you'll do a lot, if you use 2 rolls, then the car is super silent. Its self adhesive, very strong glue. You'll have to do that on the doors and firewall (behind dash too).

The car will gain about 20kg of weight though.

other brands for good insulation are : standardplast, silentcoat,...all use good adhesives and the instalation is really simple, all you need is a clean surface.

do i cover the WHOLE inside with no breaks, one of my mates said i need a layer of closed cell foam and some multi layer vinyl - do i really? 20kg is no problem as i will go on a diet.

In last few years, the development of sound insulating materials went far from normal tar based crap.

Usually when I did insulated a whole car I went with strips on the roof, doors and rear fully, firewall and tunnel on a bmw always full (less heat inside), and again strips on the floor, for a E21, you will survive with the 0.5m x 5m roll. A few strips on the rear arches and rear wall and you are done for a small ammount of money but again big results.

If you can find, try to get armaflex for the floor (so the original 30 year old insulation out, this one in and cover the floor with armaflex (foam style insulation, light and good).

I really screwed up in my car the first time I did that, because I didn't knew I'd put such ammount of money in the car, so for the end of this year, I'm planning to do exactly what I wrote to you.

excellent - so the plan is.

1.take out the original sound deadening, and clean up surface.

2. cover 50% of the large panel areas (floor / boot / under rear seat / seat dividing panel and parcel shelf with strips of the stiff reflective sheet, inside the doors on the outer panel and seal all the gaps on the inside to stiffen the door frame. also the tubs in the rear quarter panel.

3.cover the whole thing with closed cell foam - such as this? http://www.ebay.co.uk/itm/sound-proofin ... 46165508a3

4. fit some mass loaded vinyl in the cabin to seal the boot and engine bay and the floor. http://www.ebay.co.uk/itm/Soundproofing ... 4897.l4275

6. at one point get brave enough to remove the mint headlining.

total weight will be higher but im unable to hear anything since i took most of my knackered old insulation out, car isn't a track car but i want to make it as comfy to be in as i only really do long road trips and after a couple of hours you do get tired.

The total cost is about 150 pounds and a whole weekend with a friend helping.

1. check
2. check
3. check
4. I'd rather use more alubutyl instead of rubber mats, on problematic areas you can overlay them.
6. until it's mint, leave it up there

i will make a start on this in a couple of weeks time, no way i want to do 1000 miles in one weekend without it

i feel your pain, was last weekend on the seaside, 1 day, 500 km, painful experience, I could hear only things over 100 dB for a few days

im following the guide on this website

http://www.sounddeadenershowdown.com/

1.Control vehicle component - mostly panel - vibration and resonance.
2.Block air borne sound.
3.Decouple objects that would otherwise transmit vibration or make noise themselves by making intermittent contact (rattles).
4.Absorb.

I have ordered the following

1 - silent coat sound deadening matts which will be placed around the car (but not covering the whole car)
2 - closed cell foam
3 - Make sure everything is tight (but I have very little in the way of rattles to begin with)
4 - I ordered a 5kg sq/m of Mass Loaded Vinyl to lay over the top of the closed cell foam

Work starts this weekend.

the results of this i will be following with interest...

Not exactly looking forwards to it if I'm honest. Going to make a start this weekend.

Got my mass loaded vinyl and the sticky foil backed rubber pads. Just waiting on the closed cell foam.

any news?

Well I was going to start but I ended up getting busy with other stuff. This has been postponed till next weekend

I used stuff from b and q it's not sticky or anything it's just floor sound proofing tiles cost £10,some "professional" car audio guy was trying to sell me some for 50 a pack so thought I'd rather chuck a £10 under the floor and it works great!

hi guys I have finally managed to complete this task.

it has made a massive improvement, I can now hold a conversation on the motorway without shouting. the car seems a lot nicer and I don't think I have harmed performance at all.