Soundproofing to reduce road noise and boominess?

BMW i3 Forum

Help Support BMW i3 Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

SuperPoly

Active member
Joined
Oct 1, 2021
Messages
40
I find a lot of the sounds in the i3 to be "too much" when driving over rough surfaces or at highway speed.

Has anyone attempted to add soundproofing material (mass-loaded vinyl) to the doors, or other areas?

One other thought to reduce boominess over bumpy roads was to add butyl sound deadener to parts of the frame.

Since the frame is carbon fiber re-enforced plastic I am wondering if it would be effective as on traditional metal frames. The boominess tends to come from the rear part of the car.
 
SuperPoly said:
Since the frame is carbon fiber re-enforced plastic I am wondering if it would be effective as on traditional metal frames.
An i3 has an aluminum frame. The suspension, battery pack, aluminum frame rails, etc., form a "skateboard" base upon which a CFRP passenger cell is bonded. The source of the booming over rough roads might not be easy to identify.
 
I find a lot of the sounds in the i3 to be "too much" when driving over rough surfaces or at highway speed.

Has anyone attempted to add soundproofing material (mass-loaded vinyl) to the doors, or other areas?

One other thought to reduce boominess over bumpy roads was to add butyl sound deadener to parts of the frame.

Since the frame is carbon fiber re-enforced plastic I am wondering if it would be effective as on traditional metal frames. The boominess tends to come from the rear part of the car.
I wonder why there are so few entries on the Internet about the loudness of the BMW i3. Everyone thinks that if there is no combustion engine, there is perfect silence. However, the air noise is significant. I was surprised how loud it gets above 100 km/h. Driving at 120-140 km/h for a long time tired me. I was and still am surprised that an electric car is so poorly soundproofed. There is practically no soundproofing in this car, compared to even the E46. Which worried me. At first I thought it was tire noise. However, I realized that I was starting to be disturbed by the cars overtaking me. Previously, I didn't even pay attention to it in a normal combustion BMW. This got me thinking. I dismantled the wheel arch door. The door has nothing to mute the sound. Just a white rag. The external plastic profile is not as tight as regular metal doors.
I really like the bmw i3 car. Driving at 70 km/h is pleasant if no one is driving next to you.
My previous combustion engine bmw3 has bituminous mats and additional felt installed everywhere (factory). I'm surprised the i3 doesn't have anything like this.
I will soundproof the elements one by one until I achieve a pleasant ride at a speed of 140 km/h.
 
I doubt that the lack of soundproofing was any less than a deliberate decision by BMW. Its main competence is as a city car. I have no doubt they did a trade-off: weight versus soundproofing - and decided that they didn't want the car to lug around kilos of soundproofing that their intended target buyers would hardly ever notice.
 
Wind noise takes a back seat to road noise in my opinion. The aerodynamics are really not that noisy compared to many cars. It was never marketed as a 'luxury model' in any case - whether buyers wanted to believe it is one or not.
 
Seeing how the range drops off above 60 mph or so, I don't usually deal with too much wind noise. And I find I get to my destination faster if I don't have to stop and charge on the way. If there were a whole bunch of fast chargers around here I might go faster and think of the noise more, but that's not the case for now.
 
Please keep us updated.
Ok, I will keep you informed. I'll be sure to soundproof the door. This is where I feel the side noise coming from when someone overtakes you and at speeds above 100 km/h. The second step will be the front wheel arches and that's it. They generate tire noise at higher speeds.
 
I doubt that the lack of soundproofing was any less than a deliberate decision by BMW. Its main competence is as a city car. I have no doubt they did a trade-off: weight versus soundproofing - and decided that they didn't want the car to lug around kilos of soundproofing that their intended target buyers would hardly ever notice.
The weight of the materials is not that big. 10-15kg is max. So negligible weight for comfort.
 
Back
Top