Deadening on the pillars

Deadening the pillars is becoming a very difficult task on modern cars. My idea today was to deaden the A, B and C pillars but on the A pillar there was little space available and the airbags were there, and on the C pillar the airbags are even larger and there was no space available at all.

My idea when deadening the pillars is to improve sound quality (in case of the A pillars), reduce airborne noise and since both the B and C pillars are very close to the passengers ears it's nice to block any noise that might enter the cabin thru there.

The A pillars

On the A pillars there is absolutely no deadening from factory, not even in the trim pieces. There is space available on the drivers side, above the airbag, but on the passengers side there are cables routed thru there so space is at a premium.

Funny thing that I didn't notice on the doors, all trim pieces that go on the right side of the car have a white sticker with a bar code, the ones that go on the left side have an orange sticker with a bar code. Beats reading text looking for Left or Right on the assembly line, just use colours. Clever thinking.

These are the A pillars without the trim.

A pillar, drivers side
A pillar, drivers side
A pillar, passenger side
A pillar, passenger side

I used silver Dynamat, I still had one sheet and it's not going to waste. On the drivers side I had decent space and got almost full coverage. On the passenger side I will let the picture speak for itself.

Nice Dynamat coverage
Nice Dynamat coverage
Tiny amount of Dynamat
Tiny amount of Dynamat

Since the tweeters are mounted on the A pillars I tried to add as much Dynamat and Dodo Super Liner I could behing the tweeter to improve sound quality. These Bose tweeters sound very harsh, Focal is known for harsh sound tweeters but they have more clarity than these. I'm trying not to replace them, but who knows...

After Dynamat, Dodo Super Liner (6mm) was added on top.

Dodo Super Liner on the drivers side
Dodo Super Liner on the drivers side
Dodo Super Liner on the passengers side
Dodo Super Liner on the passengers side

After that It was just a question of putting the trim back in place.

Trim back in place
Trim back in place

B pillars

On the B pillars there is more space available as there is only the seatbelt roller, guides and the seatbelt itself. The B pillar is divided in two parts like in the Citroën C6, so the setup was very similar.

I divided the work in two steps, first the lower half of the pillar, then the top half of the pillar.

This area is always filled with lint that gets transferred from the clothes via the belt and ends up in either the roller at the bottom or on the trim pieces so there is always some extra cleaning to be done and special care to avoid any butyl rundown to the seat belt or roller.

Unlike the A pillars the bottom part near the seat belt roller has some deadening material.

Trim piece from the top part
Trim piece from the top part
Trim piece from the bottom part
Trim piece from the bottom part

So, first I installed Dynamat on the bottom part and then Dodo Super Liner. Behind the seat belt there was no space for either Dodo Super Liner (6mm) and the thinner 1/8" Dynaliner (3mm) would still rub the belt in certain conditions, so best to avoid any future issues and leave it with Dynamat only on that area.

Dynamat Extreme on the B pillar
Dynamat Extreme on the B pillar
Dynamat Extreme on the B pillar
Dynamat Extreme on the B pillar
Dodo Super Liner on the B pillar
Dodo Super Liner on the B pillar

On the top part was the same, Dynamat Extreme followed by Dodo Super Liner.

Dynamat Extreme on the B pillar
Dynamat Extreme on the B pillar
Dodo Super Liner on the B pillar
Dodo Super Liner on the B pillar

And then, as always, everything back into place.

B pillar trim back in place
B pillar trim back in place

The C pillars

If you have a Opel Ampera or Chevrolet Volt and want to deaden the C pillars, just forget it. There is absolutely no space available with the massive rear curtain airbags and a lot of electronic cables. At least there is some deadening material on the trim pieces from factory to help reducing noise, but that's it.

C pillar interior
C pillar interior
C pillar trim
C pillar trim

At least I got to see how it comes apart, useful when I deaden the roof of the car.

Weight added and the results

On the A pillars I used about 100g of Dynamat and very little Dodo Liner in the two pillars. On the B pillars about 300g of Dynamat Extreme and less than 100g of Dodo Super Liner. Very little weight added.

At 80 km/h there is no difference as the wind noise is very muted, but at 120 km/h the wind noise has reduced substantially at the front of the car, where the meter is. It now reads 61dB, a 1dB reduction. I was not expecting such a good result, but from experience on both the Peugeot and the Citroën deadening the A and B pillars really helps to reduce the perceived noise on the front seats. Now the prominent noise is from the tires at the rear, so probably my next step will be deadening the boot floor.

In terms of sound quality there was not a big difference, I think the problem is really with those tweeters that lack clarity and definition.

Opel Ampera
Done in 21 of October, 2018