Morris Minor Owners Club

Can anybody recommend a decent soundproofing product ? I bought a roll of that hairy stuff a couple of years ago at the national rally but was never too impressed with it! Anyway, the pickup cab is stripped out at the moment so its a good time to put in some decent stuff

There is carpet soundproofing available that has thick wrinkly rubber coating on one side. I have seen this in a John Lewis warehouse. It is about 3/4 inch thick and should be excellent for soundproofing a car. As with all this sort of stuff the results are only as good as the thoroughness of the work. You will have to do the WHOLE bulkhead to get any appreciable results and that is by far the hardest part of the car (typical ).
Part of the problem lies in the area around the pedals where a thick underlay plus carpet can restrict the movement of the throttle pedal.
The other area worth doing is around the boot and back seat where you can get a fair amount of boom from the tailpipe if your exhaust is a little on the short side.

Make sure you don't have any water leaks before adding any sort of absorbant soundproofing, otherwise it'll soak up & hold the moisture.
There is a type of closed cell foam insulation available here that has a reflective material (like aluminium foil) on one side designed to reflect heat. Might not be much use in the UK but it seems to help out here. We used to fit it to the 'Press' Range Rovers under the centre console to try & stop the heat coming through. The left overs went nicely into the Morris.

Make sure you don't have any water leaks before adding any sort of absorbant soundproofing

Very sound advice!! I've seen cars with loads of water under the carpets.

I have a horror story from a Eurobox where the sound deadening has a rubber top coat and there were rubber mats on top if the carpet so the problem was hidden when I bought. It showed itself in 2 ways:
a) the windows were misted up on the inside every morning for 3 years
b) when parked on a sideways slope the car filled up to 2" of water - above the carpets

I put some drain holes in the floor but the foam didn't dry out during the 3 years I had the car. The only way to fix it would have been to take the interior out (not easy on a eurobox), then to find the water leak, and in parallel to wringing the foam out and leave it to dry for a fortnight.

So if any water is getting into the car - make sure that is cured before adding anyhing absorbent to the floor!

I have a horror story from a Eurobox

I had this on two euroboxes, caused by a leak on the membrane behind the door cards. The underside of the carpet was rubber coated and the 3/4 inch sound deadening was soaked and mouldy
Fixing the new membrane so it was 100% watertight was a harder job than replacing the entire front suspension