I would like to install the magnaflow hfc on my g37. My car is a lease for 4 years and i would like to know if I can buy and get a shop to do the install but after the 4 years ca i bring it back to nissan with the magnaflow or do i have to remove it and return it with stock exhaust?

 

you can do what you want, but you should remove it after your lease is over and sell the part by itself.. so you will lose since your car isn't fully stock and you spent money to put in an aftermarket part...