Sound Deadening Options? Options

[ThinAir]

This is me, picking up my freshly repainted 914 from PMB Performance.



Now that it's home, it's time to start putting things back together.

I'm looking for sound deadening solutions for the floor and interior back panel. I'm planning on keeping the interior back panel, but figured this would be a good time to enhance it with some sound deadening capability.

My searches haven't been very successful. I'd appreciate it you guys could offer some advice or point me to previous threads on the subject.

[r_towle]

Lots of good info here and online.

My two cents.
Sound deadening is about stopping both sound waves and vibration.

Certain materials stop certain sound waves.
Product like dynamat at rubber-foil which blocks two types of sound waves.
It also builds up the thickness of the metal to reduce vibration.

I would suggest a multi prongs approach.
Ceramic spray on sound deadened on the engine bay side.( lizard skin is on product)
1/2 inch foil faced mat on the engine bay side (914 rubber has that)
Dynamat on the inside.
Then both blocked more types of sound waves, but reduced vibration twice.

After all of that, the window is really loud.
A double pain would fix that..

In the end, a loud stereo or earplugs work really well.

[ThinAir]

I would suggest a multi prongs approach.
Ceramic spray on sound deadened on the engine bay side.( lizard skin is on product)
1/2 inch foil faced mat on the engine bay side (914 rubber has that)
Dynamat on the inside.

Even if it would be helpful, no treatment on the engine side for me. I just finished paying to fix rust in the firewall so we're not going there again.

I have pretty reasonable expectations of how quiet a 914 can be so I think I'll be fine with interior treatments only.