What are the top mods for maximizing horsepower on a Nissan GT-R?

I recently purchased a Nissan GT-R and I'm looking to increase its horsepower. What are some recommended modifications and how much horsepower can I expect to gain from each?

One of the best mods for increasing horsepower on a Nissan GT-R is an upgraded turbocharger. You can expect to gain anywhere from 50-100 horsepower depending on the size and brand of the turbo.

Installing a cold air intake can also give you a noticeable boost in horsepower. You can expect to gain around 10-15 horsepower with this mod.