Strat - Will Blocking Trem require setup?

if your trem already lays flat against the body, then no.

If your trem floats and there is space between the bridge and the body, then yes.

I setup mine to have the bridge flush, so I could only bend the pitch down. When I put the block in there, I needed no setup.

Thanks,

Mine isn't flush, it is angled up towards neck, meaning I can only increase the pitch by pushing down on the back, can't really bend the pitch down. Am I safe to assume that when the tremolo is blocked, the bridge will be lower, and the strings will be closer to the base? I was hoping that when the trem is leveled out, that it was somehow hinged so that the bridge would still keep the strings at the same hight.

You could block it in the position that it is now and not have to change your setup. Just use a hardwood block between the spring side of the trem block and the trem cavity that is the correct thickness to just maintain your current position and then either tighten the claw screws or add an extra spring. If you are looking for improved sustain or string resonance and you have a vintage trem, try tightening the two outside screws holding it to the body, you can change how your strings resonate the guitar body by experimenting with this ( if you go too tight, obviously, your trem won't move very far and you could dent the wood underneath ).