That is a serious diet if sacrificing the weight of the carpet makes a difference.
There are a lot of good sound deadening materials available these days, depending whether you want a combination of sound & heat insulation; Dynamic Controls (Dynamat), Boom Mat A search at somewhere like Summit Racing or Jegs will bring up plenty of choices and their own brands too.
Also spray on sound deadening e.g. Lizard Skin
I just refitted the interior of a GT40 replica, the carpet I used is "Ozite" it is a stretch carpet with no backing and only weighs 18oz/sqyd. I got it and the vinyl etc. I needed online at www.YourAutoTrimStore.com
Julian
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