Transforming i3 into a vault

[electronchaser]

As the subject line describes, I'm going to be stripping the interior (just waiting for MLV to arrive), upgrade speakers, and treat the body panels for some serious sound elimination. During higher speed travel, the interior is just too noisy, and I hear most of the intrusion from the sides, doors, more than from the road. I'm also aiming to dampen the body panels to minimize distortion and resonance.

I'm curious if the thermoplastic panels on the exterior of the car will fare ok with a layer of butyl , closed cell foam and mass loaded vinyl layered up on it. How difficult is removal and installation.? Something that can be done with just clips and a few screws?

I'd love to remove the front fenders and line the wheel wells as well.

Also would anyone know what material that thin piece of white cloth is right behind the door panel? I'd like to also buy more of that cloth stuff as that sort of material works great in absorbing high freq sound waves. The ones I've tried to source are a denser more rigid fabric.

 

[Obioban]

You might be fighting a losing battle. Carbon chassis's are inherently noisier than metal ones. The i3 is the quietest CF chassis car I've been in already.

 

[Star63]

I believe the white cloth behind the door cards is Acoustic Thinsulate from 3M.

 

[electronchaser]

I believe the white cloth behind the door cards is Acoustic Thinsulate from 3M.

Thanks mate! that's it! HUGE help!!!

 

[trumpetdoug]

Any updates on what you are doing?

Doug - out

 

[electronchaser]

Any updates on what you are doing?

Doug - out

hahaha, yes def got updates. I'll leave a few bullet points, and come back with more updates and pictures as some things are hard to explain without a visual. I've actually been really busy. Doing two cars at the same time.

so from experience working on a lot of cars, for a lot of years as a hobby....I must say I love how this vehicle is put together. If you take your time, make it fun, (and buy a box of disp gloves from costco for 10$ and change them often), its a clean, easy job.

Butyl CLD tiles. IFFFF you want to do full treatment and 100% coverage, factor about 8-10 sq feet just for the front outer door skins. Factor the weight is approx .65lbs per sq ft. so you will add about 5-6lbs of weight per door from just stage one treatment. But the doors shut nicer than a 7series. (The stock doors have absolutely no sound treatment, other than a thin sheet of batting)

I've ordered a lot of material, tried out different things in different spots. went for damping in certain locations, absorption in others.

Made custom MLV for the door cards. which is the 2nd densest thing available out there after lead (currently a shortage of depleted uranium ). I believe it was about 5-6sq feet of material for each door card, decoupled with foam on both sides (overkill, but had a lot of foam),
haven't put it together yet. Should fit as foam will compress and make a nice gasket too.
(but the door card on the i3 is nice that it covers a lot of the actual door panel. On other cars, there's still metal door surface that is outside the door card area, so you can never fully treat those areas. ) *MLV adds about .75lbs per sq foot.

brought in a competition sub from a friend to shake the crap out of everything to identify every loose and resonant area on the body. once I've gutted the cargo area trim, I'll bring the headliner down and see whats going on up there.

Currently testing different materials for durability to use as cloth based liner to sandwich the front fender liners with. Currently having favorable test results with some 4mm stuff that is has resisted molding or any other funkiness for the past week. This will definitely help cut out higher freq range road/tire noise. which is insane above 75mph.

Car's a mess, looks like all the guts are spilled out. But if it even comes out half as good (since I'm working with totally new materials [carbon fiber + thermoplastics + recycled plastics]) as other cars I've treated. I'll be ecstatic.

I'll need to see how the noise from the floor area is once the upper cabin is done and put back together. Stock, its so loud up top that you can't really tell if any noise comes through the floor. Hoping the battery pack muffles a lot of it already. otherwise that'll also have to come out and get treated.

tips:
Really helped looking at pictures of wrecked i3s with body panels missing. also the newtis.info website. etc.

3m is your friend. use only 3m products. glues, velcro. Last thing you want to do is go in again because stuff came loose due to inferior products.

MLV will be the most expensive part. for the virgin, flexible stuff with zero smell, its a good 4$ per sq foot. Its very heavy, so I def don't recommend buying a big roll. Buy in smaller chunks and its easier to work with. Don't buy the inferior stuff!!!

 

[trumpetdoug]

Thanks for all this info. Really looking forward to seeing pics, if and when you can post them.

Doug - out

 

[SuperPoly]

@Electronchaser

thank you for this write up!

How did it work out? I would love to hear more about the result and the process. I agree that a lot of noise seems to come from the sides of the car (including wind, and electric motor whine).