1967 911 insulation questions

[vramani]

I am trying to locate the best match to original materials

1. Horse hair type of product
2. Felt roofing like material
3. Padding

[MTemp]

Well my first question would be 'why?', because they're all products that in no small part contributed to the rust pockets that plague these cars.

To replace the horsehair I used the bonded felt shown in the photo from any upholsterers, and to replace the 'felt roofing' I used sticky backed acoustic sound pads again available from lots of outlets. These can be cut to shape and attach themselves well. I avoided using them anywhere water might 'pool' like the inner floors. Here I just placed the bonded felt under the carpets so they can be removed if necessary to let the metal dry out. I do not think you want anything stuck to the floor under the carpets. The floor is treated with POR 15 Rust encapsulator and POR 15 Chassis Black.

I didn't replace any of the padding/wadding as all it does is provide a sponge for condensation, especially around the vent tubes at the base of the rear parcel shelf.

Mick

[platas]

Guys, who sell this ?

[merbesfield]

Here's one manufacturer.

http://www.feltech.co.th/product1.php

[37yrold911]

Is the felt better in any (functional) way than the closed-cell foam products?

[merbesfield]

Is the felt better in any (functional) way than the closed-cell foam products?

I don't know, but I read somewhere that closed cell foam does not hold water, which would be extremely important to me.

[Haasman]

Interesting discussion. And the closed cell doesn't hold water but would keep it localized/trapped. Hmmm ... the felt would help moisture evaporate?

[MTemp]

Interesting discussion. And the closed cell doesn't hold water but would keep it localized/trapped. Hmmm ... the felt would help moisture evaporate?

I thought long and hard about what to refit in the car shown in post 2. My experience with stripping several cars, and with my TR4A, is that unless you use some form of paint/coating (like Liquidskin) then any form of surface material, no matter how well you think it's stuck on, will have cavities and spaces underneath, and at some point these will get wet (condensation, window left open, spilled drink etc etc), and therefore it is vital that you can get the material out, and ideal if it can 'breathe' so at least it will eventually dry out.

So I opted for this 'bonded felt' - stuck on with contact adhesive on the vertical panels, but just cut and loose under the floor carpet and the rear seats. The bonding gives it more durability, but it can still 'breathe'. I'm sure it will need replacing every few years especially on the drivers side, but it's cheap and easy to get.

No right answer I'm sure, but this was my reasoning.
Mick

Note: I eventually removed the black sticky soundproofing from the rear seat bases shown in one photo for this reason.