I have the engine out and cleaning up the hell hole. The pad is in good condition and I am afraid if I start removing it I will just add another project I don't have time for.

Is there any benifit to changing to a foil type pad? Isn't it also more likely to get wet and rot ?

Any advice is welcome

foil = less weight and I think it doesn't soak up moisture

Yes..but they have to have an insulation value for sound...correct? Most of them are fiber backed.

I was thinking of using the same material that is used between the carpet and floor on interiors.

Has anyone tried reflectix? It's basically bubble wrap lined with mylar or some other heat reflective material. It's cheap compared to most automotive insulation materials, and certainly light. I just don't know if it would do anything to stop sound.

are you talking about the pad in the engine comp or the pad inside the car?

if you mean the one in the engine comp, i definately would remove it and check for rust near where the bottom of the pad was.

they hold the water nicely and the cars rusts right through the firewall ...
Andy

Yank it! Three out of 5 cars Ive pulled from had some level of Rot due to the Pad.
The least damaging was no holes but enough surface rust to render the single sheet firewall ...Very Thin!

I know that Dynamat makes an acoustic/heat shield for this application. Also, I noticed that Performance Products had a foil replacement heat shield for the firewall. Hope this helps.