Well it seems brakes on all cars really are my arch nemisis!
I really need help with this.

Right the full story:
Ive done a full re-shell. In the new car i have Rs turbo front discs and rear drums. Both drums have had BRAND new cylinders put in. The servo is a fully working one from my old car(took me ages to find a good one). The master cylinder is a 1.3 hcs cylinder. All lines are solid and not leaking at all. The vacuum line was also fully functional on the old car.

Basically my pedal will just go to the floor with a little effort EVEN when the engines off!!! Now first thought was servo so i swapped it for another good one(this one being fully working on the car i removed it from so deffo no probs with it). Again this didnt help it, so i put the new rear cylinders on and again no difference! I have used over 5 litres of brake fluid bleeding the brakes each time. I have done the 2 man method, back bleeding, and naturally leaving a nipple open for a good resovoir of fluid to gravitationally come out.
Everything i have done has had NO EFFECT what so ever in the pedal pressure! When the cars idling and if i continuously pump the brake its fluctuates the revs and sometimes even causes it to stall
I have tried two master cylinders now as well(tho only one i cud guarentee as fully working) and again no difference! I checked the vacuum line and there are a small surface slits/scratches but nothing that looks like it would actually have penetrated the wall of the line to cause a leak. The valve in the vacuum line is also working.
PLEASE SOMEONE, ANYONE throw your ideas, advice, knowledge at me! im desperate! Ive had a lot of problems with brakes but none that havent been fixed by replacing everything

Many thanx, a very wound up and stressed out Harry