Black Plastic Firewall Insulation?

[AlcanDD]

Hello all-
I have a 1996 KC SE (KA24e 5 speed manual). I am working to take out my engine and transmission. Toward this end, I decided to remove my front carpet. The pads beneath the carpet appears to be attached to the carpet, as they mostly came out with the carpet. It was different in the firewall area though. The carpet near the firewall was not connected to the pad. Instead, there is (was) a sheet of black plastic material that appears to be connected to the padding, between the carpet and the pad. This material has become brittle and is mostly in pieces in the floorboard.



Since the black plastic material is only in the firewall area, I assume this is some sort of a heat shield or insulator. Even though it is largely disintegrated, I have not noticed any abnormal heat in the cab.



I have searched the forum with countless combinations of carpet, insulation, shield, etc. I have seen this stuff mentioned a few times, but I have not found out what is is called or found out if it is something that can be purchased. Perhaps this information is in forum, but I couldn't find it. I also did not find it mentioned in the FSM, and I could not find a mention of it on Nissan parts websites.



So, I have questions:

1. What is this black plastic thing called?
2. Does it really do anything? Is it for heat insulation? noise control? fire retardancy?

2. Can it be bought?
3. Does anyone know what it is made of?
4. If it's not available, what should be used to replace it? I've been reading up on sound deadening, and it looks like some of these products can handle heat and are fire retardant. Would one of these be a viable option? What have others used to replace it?

[dvdswan]

It's heat insulation from the engine compartment to the in the inside of the cab. The foam is about 3/4" thick. If yours is denigrated, I would look for one at a junkyard. Buying new, either it will be difficult to find or pricy.