Can you fix the height of the passenger front seat
Do you mean that it is broken? Or you want to fix it (lock it) to one height so no one can ever change it?
I think Joe wants to have the entire seat higher than it came from the factory.
But since I don’t have a 2014 Lia Optima one poster thinks I should not reply.
But I will anyway. Joe if I am correct that you want the entire seat higher contact a body shop that can use proper spacers and tempered mounting bolts.