I know this subject has been covered many times, but let's beat a dead horse...

Finalizing some things before installing the wiring harness on my GT build, and need to make a decision on sound and/or heat control. Suggestions or opinions on the best materials for this and installation tips greatly appreciated.

For instance: better to install on the engine bay side? Less effective if on the cabin side? Etc., etc. Interior bulkhead will be covered in Perlon, floors will be rubber mats. It won't be a quiet place, but a little mitigation is the goal.

Thanks for any advice the 914 World brain trust might offer.

These threads cover a lot, but which materials are best? http://www.914world.com/bbs2/index.php?showtopic=342295 http://www.914world.com/bbs2/index.php?showtopic=361863

Who has one of these? https://www.rix914parts.com/store/p29/914_F...uction_Mat.html Is this material available in sheets to apply to the interior ?

If you look at the below linked thread and slide down to Roblav1's post you will see his use of 80% wool gray felt (1/4"?) from Mcmaster over Dynamat. This looks like a nice solution and look:

http://www.914world.com/bbs2/index.php?sho...359&hl=wool

McMaster page:

https://www.mcmaster.com/catalog/129/3984/9248K222

I used the self adhesive Noico sound pad’s found on Amazon. Come in black or shiny aluminum finishes. Easy to install and trim. Still working fine after 3 years.

There is no one best material.

Material selection depends on frequency of the noise and whether it is transmitted through the structure or through the air.

NVH Generalization:

Mass damping and constrained layer damping for frequency < 100 hz transmitted structurally. Example: floor pan transmitted noise coming in through the suspension.

Barriers and absorption for frequencies >100 hz that are transmitted through the air. Example: high pitch alternator whine, 911 fan noise, 914 fan noise, tire sizzle noise, valve clatter, etc.

I would suggest all.
Spray on lizard skin (ceramic spheres in paint)
Dynamat inside and out
Wool mat
Rubber liner

That covers many/most frequencies and stops the vibrations.

The last bit is the glass, which is what it is.