Did'nt Davrians use foam to add stiffness Davrianmad???

Yes they did, my MK4 built in 1970 has both sills filled with foam, without the foam on good B road you could pop the windscreen out (windscreens are not bonded, bonded screens add strength). I have never had that problem and it seems very stiff, jack a front wheel up and hole side of car lifts. My Mk4 though is road car and therefore made of very think glass fibre, as for my MK7a which is of race specification. Before I reinforced the floor on sunny day you see the white lines through the floor as you change lane, it has got no foam in sills the body is paper thin but handles really well.
If a fibre glass box twists, fill it with foam, it becomes very ridged, that is the idea of putting foam in the sills. If you are going down this route get industrial foam nozzle from Tool station or Screwfix and buy the industrial cans, much cheaper and more controllable.

has anyone tried this and if so how much of a difference does it make? might have to make a trip to screw fix tomorow evening nice cheap mod to do

Check three posts up

ah right wont bother then i picked mine up today and drove it home for the first time with the roof making a right racket turns out the person who s9old it to me neglected to mention it wasnt even bolted down

Sounds like a project right enough It actually sounds very similar to mine when I bought it except that mine had never been on the road. I discovered that the roof had never been bolted down when I jacked up one corner and the roof popped up I think that's known as chassis flex....

rofl aye sounds like it and yes ive definately got a project on my hands need to check the valve clearances first and get the brakes sorted seen as they are very very poor but atleast i had a grin on my face

With regards the filling of the cills with foam, if you end up tearing down the whole car as a rebuild and you can re-route the services in the cills to somewhere else then I would give it a go. I just got fed up with the amount of flex with the soft top on and I don't really like convertibles that much anyway (personal prefrence), however I need to replace a couple of the heater hoses on my one that go down the cills and from what I can gather it has only been about ten years since build and they are perished, not leaking but not far off failing soon, if you fill the cills you would never get to them or be able to re-route easily. Remeber my one is a K3, earlier Rossa's maybe different.

The grin factor in always good.

ok well theres alot of other stuff that needs my attention before then but i will definately have a good poke around and look into it thanks for the advice.

Pipes run down the centre tunnel on a Rossa, so no problem there.

Allen

well a couple of cans of foam will be finding there way into the sills then = had a nightmare remove the rear tub yesterday ot exactly easy to get to the bolts inside the turrets :/

If you look at my thread, in the pic below the one of the dash metalwork you'll see porthole covers on the rear turrets that screw off to give access to the mountings. The porthole assemblies were around a tenner on ebay (they're meant for a boat ) and I made the holes using a trepanning tool that cost around a fiver, again on ebay. You can see the open holes on page 2. Access is now a doddle and there's also two small storage areas if you need them.

well after much debate last night and a few pints ive decided to knockup some plates with captive nuts welded to them which i am going to rivet to the inside of the turrets i agree cutting holes in the turrets gives easy access but doesnt it compromise the structure?

It doesn't seem to compromise anything. It's a fairly long standing mod and I've seen no adverse reports. It's very strong in that area.

then it would probably be easier if i do what you,ve said then i,ll have a good look before i start cutting holes lol