You've a couple of options. You could trace the logo and then photocopy it, enlarging it by the percentage you require, then trace that on to the wall. Or, if you have access to an overhead projector you could use your tracing as it is and just project it on to the wall, tracing it in from the projection.
You could divide the version you have into a grid of smaller squares, pencil the same grid using larger squares onto the wall and use that to copy the content of each square from the smaller version onto the wall.
thanks everyone for your help.I,ve just remembered those sort of drawing frames where you draw round the outline of the item to be copied and the frame produces a larger copy for you .It had 2 pencils and about 4 sections to the frame and you could increase or decrease the size .I can,t remember what they were called , maybe i could buy one and use that?
I know the gizmo you mean; I'm working on the name of it. We had a yellow one that came with Tom & Jerry pictures to copy. There was a special board as well to screw the pivot (fulcrum?) onto. I think you'd have to make your own, though, to cope with the the ratio you're talking about...