Ive just seen this mentioned by @vanorak on another thread. I haven't fitted any but I'm able to take the firewall off again easily to put some in. What's the usual material used or is anything better than nothing ? Anyone have a bargan basement solution with good results?
silent coat from ebat is good 10 A4 sized sheets for about £15 .....you wont even need a quarter of that for the fuel tank area
you can use silent coat/dynamat type stuff on the rear bulkhead (behind the tank) and the cargo deck (above the tank) with the added benefit that it doesn't interfere with any flooring/carpet etc. in the living compartment. The tank itself can be treated with a few strips of the same stuff as can the wheel arches and the firewall panel itself....if you want to go one better, make up some 'parcels' of Rockwool or Polyfill (the stuff they use for filling speaker enclosures) and drape them over and around the tank...these need to be sealed in plastic to prevent moisture ingress. Rest the tank on closed cell foam blocks before reinstalling....and put some between the tank and the straps..... At the end of the day, you're hard pressed to prevent engine noise as there's a mechanical connection between the engine/trans and the body, but you can definitely reduce the overall noise in the cab by absorbing some of the more intrusive frequencies that emanate in the tank compartment....it acts like a big metal resonator, as does the tank. If the engine's out, pull the original 'sound deadening' material out that's sandwiched between the cargo deck and those holey plates, and replace with heavy grade (5-10KG/m) Mass loaded vinyl, plus some soft closed cell foam....ie used code 4 lead, which is perhaps OTT but it works exceedingly well Bargain basement solution is to buy a long roll of roof flashing and line the compartment with several layers (use a border roller to get rid of any bubbles) and then blag some Rockwool batten from the attic....bag it up in polyethene and seal with gaffer.....old Karrimat (camping mat) is a good medium density closed cell foam....this can either be stuck on top of the flashing with spray glue, or cut to size and used to 'line' the area
Finished up a Mk1 Rabbit rebuild in the spring. We used Roofers "ice and sheild" starter strip all over the floor and back area. It comes in rolls and is a black tar , same thickness as the dynamax, with the same sticky under surface to stick on the tin, but the top is a plastic coating, not foil. For sound proofing and water tightness it's working a treat, no moisture will stay in or on it, kills the road noise. It runs (here in NS Canada) about $60.00 a roll, enough to do a Van. Just a thought!!!
