more front arm travel/droop
 

Why is it that most cars do not allow front arms to go lower and are limited by the shock length? Why don't they let you experiment with lower downstop value of front arms?
I understand that most brands want to restrict the travel, any good reason for this?

Too much down-travel will cause drive shafts and steering to bind.

I understand but this is when you go too far.Some manufacturers make optional towers and longer shocks to allow more droop.For what type of use do they promote these parts for?

Now that's more understandable.

The parts I know just increase shock volume and place the top of the shock further up, effectively decreasing the effect of the bladder or preventing the piston retainer nut to hit the bladder.