How stiff springs on Scuderia without revalving?

How stiff springs can you put on the original dampers on a Scuderia without the need to revalve the dampers?

I never got to do any changes of the springs and dampers last year on the Scuderia. Ended up putting on wider Trofeo R 245/35-19 and adding more camber and toe-out in front.

Not more to do now without some real changes i guess. Plan is to try to put wider 9" wheels in front and to squeeze in 265/30-19 Trofeo R's.

This will probably mean I need the car to be stiffer. A complete set of Öhlins dampers is out of reach so I would like to try to go as stiff as possible using original dampers.

Anyone that has gone berserk on springs and found out how far you can really go ;-)