Anyone know how much pre load you can have on a vulcan ?

The spring I took out looks in perfect condition but there was no pre load at all and I have read in a few places that there should be ?

Cant say for certain that the spring I took out was an original.

I have used a spring that closely matches a titan number 8 ,the size often recommended for vulcans but would need different guides to a standard spring .

There was about 40mm pre load I was using a compressor so got it in without much fuss.

So I have had the guides made for this spring and on checking I can see the guides are not touching so it has to be the spring it looks completely compressed inside the piston .