Foam in hoops

[JonnyT]

I am sure that I have seen threads on here that suggest that some people put the expanding foam stuff in the rear hoops before they are attached for to the car. I can't find the thread on here because search doesn't seem to be working. What was the purpose of this and what is the general view about doing it?

Thanks

[nbracken]

Jonny the purpose is to stop teh noise from the rear diff travelling up the roll hoops which are right behind your head. I have heard from others that it is somewhat effective but haven't done it myself.

[wilf]

Nigel is right - the diff is bolted directly to the frame in our cars, whereas it was in a rubber-mounted subframe in it's original useage. The roll bars bring large amounts of diff noise up to your ears, can be annoying/worrying.

If you don't want to use foam (can be messy), then pulling strips of old carpet through the hoop works as well.

[chedz]

I went to B&Q and bought a couple of those foam pipe lagging things from the plumbing section and have stuffed them in. They are about 50p for a 1m length and fit inside nicely (the ones for 15mm pipe), they take a bit of shoving mind. They also come out should you ever need to get them out....can't think why you would though
Graham

[Silent Partner]

Our mast is hollow and the ropes banging against it made a hell of a racket so it is filled with packing beads like a bean bag. I spose it could work and is less permanent than expandable foam.

Just a thought!

[nbracken]

Hi Wilf - trust you are well - seems forever since I've been in the UK anywhere near Cobs but I'll be over in teh summer for a couple of weeks and I'll try and hunt some of you down.

By the way what colour carpet do you put inside your roll bar?

[RichardG]

If you do down the expanded foam route remember to make sure the insides of the tubes are damp as the foam need it to set properly.

[tarmacscratcher]

Originally Posted by Silent Partner

Our mast is hollow and the ropes banging against it made a hell of a racket so it is filled with packing beads like a bean bag. I spose it could work and is less permanent than expandable foam.

Just a thought!

A sail powered cobra, that's novel.........(kidding)

[Robin427]

I turned my hoops upside down and filled them with water to get them damp - then drained the water out. With a long plastic tube attached to the foam can, I filled them up by slowly drawing the tube out with the trigger pressed. I get no noise through them at all...

[Wilburn]

Does this apply to all Cobra replicas? I have a Dax De dion build in progress with twin braced roll hoops.

Paul