Exhaust excessive noise - anyone tried this?
 

I'm one of the many who have got (at least) a replacement rear silencer, which is a pattern part (not original Rover). Thus I have lost the quiet ride that the original had. Car is a Mk1 2.5 KV6 Connie btw. I got it last December as an excellent replacement for my last one which dumped its oil, but that too had a similar noise problem. On Thursday I had a look & listen underneath, and tbh I couldn't really see a problem with the exhaust, but there is a bit of a drone from the rear silencer.
I found this on ebay - plenty of alternatives - which seems to be a wrap on outer tape for exhausts, with heat dispersal properties (for racing), but also acts to quieten exhausts. I am wondering if this is a viable option worth doing to our silencers, perhaps even the pipe too?
Any thoughts or experiences anyone?

https://www.ebay.co.uk/itm/1-Roll-Du...sAAOSwmphaLh1b

How is this going to quieten a noisy exhaust, I cannot see it myself.!

That is why I'm asking! But, having read through the descriptions of the products on a number of ebay items, I can accept that it does work - but is it in the right way for what I'm looking for? Presumably the noise within the pipe/silencer is muffled by the extra thickness of absorbent wadding on the outside. Various descriptions of its use refer to m/cycle use in "taming" noisy bikes. There also seem to be "inserts" which can be pushed into the silencer, to better redirect the sound into the muffles of the box.
I'm no expert, just wondering what works and how well? I was idly thinking, before I searched, about the adding of double glazing to a house window to counteract traffic noise (& that works), so wondered if there was a way of wrapping something round the outside of the exhaust system to quieten it more..

Guess as the original rear silencers were double skinned and I guess aftermarket ones are single skinned adding exhaust wrap might quieten things a bit. I'd only try it if the new rear silencer you have is stainless though as exhaust wrap has a tendency to hold moisture,more so under rear of car than on exhaust manifolds (headers)at front of car where it's normally used,making mild steel exhaust parts rust quicker than normal.
Wear gloves,overalls etc if you do use exhaust wrap or you'll be itching/scratching for ages ! I was after wrapping the headers on my V8 with it

I had a similar noisy exhaust on my 1963 P5 Rover generally due to it being stainless. I strapped on a heavy Cast iron rod to the pipe and that worked by reducing the droning. I feel that you may be experiencing similar. The OEM rear box is very heavy and as mentioned earlier double skinned. My Connie rear box has had the outer skin rusted away for a few years but still passes the MOT as there are no leaks.
Using the bandage you have found is more toward heat insulation so has minimal sound insulation, I fitted some to a header with that effect, however I would suggest using copious amounts of exhaust cement not only to help adhesion but also to give a bit of weather proofing.
Good Luck!

AND, a mask over you nose and mouth! I was coughing for days after wrapping my motorbike exhaust headers.

A large part of the original pipework was also double skinned

That exhaust wrap is for header pipes and front pipes. Not intended for wrapping round silencer boxes btw. The only thing that will succeed in doing is to hasten the rusting of your silencer box by retaining moisture.

I would imagine IF it did work, I imagine it would work by dampening the noise/vibration, but as Avulon says, as it would be cooler than the manifold and under engine pipework, it would lead to a lot of moisture retention.

I wonder if extending the tail pipes a little would reduce droning. The pipes on a 75 do not extend past the bumper, and it makes me think that the tail pipe length could different on aftermarket ones. With the exhaust resonating behind the bumper. I had an old piece of plastic pipe which I clamped to my mother's droning exhaust, using two screws through it as a clamp. It worked a little, well at least until the first speedbump lol. But in her car, it partially proved my theory (it only reduced it, didnt eliminate).

Chuckles also mentioned a point that should help at least. By welding a heavy piece of material to the box, would help to dampen sound and vibration.

from my experience with Wrap , I had my whole 4 branch exhaust wrapped on my lil Fiat, to try to combat underbonnet heat .


It seems to accelerate corrosion of the pipes , and it also absorbs damp during the cold/wet evenings.


And when you start up you get clouds of steam for a short while :duh::D



Took it all off after a couple of weeks & still got a roll left in my shed .;)


C.