I've been considering replacing the stock sound-proofing panels under the bonnet with another material.
Although easy to work with Dynamat however is too expensive for me.
I see other Renault owners in the BG forum, have used another product for sound proofing - the trade name is Firex
by Sanifoam. Although people here are sceptical about Turkish products, it seems to be cheap and efficient solution to sountproofing an engine bay. It's fire-resistant too.
That's what it looks like:
Here, this materials costs about 4.50 EUR/m2. From the producer's site I see the vendor for the UK is PriTex
, so I guess you can check their price for this insulation.
PS. I don't want to make advertisement with this post, and I'm not affiliated with any of the producer/supplier in any way. If mods find posting links here to be out of line with forum's policy, please do let me know or remove them.