Matthijs,
Good to hear that my setup tips helped you out. If the car is too easy to drive just go little bit softer on the front spring.. pink/silver would be something you could try.
I think that a spool in front would be a bit faster/sharper for stock racing then a gear diff...Not to sure though, I only used gear diff in rear until now.
Still using D-D in rear?
TomEG,
I usually measure the droop with Hudy blocks, on the end of the suspension arms underneath the pin that goes through the hub. 99% of the time I use 6 in front and 5 in rear..