What are the best modifications for increasing the horsepower of a Nissan GT-R?

I recently purchased a Nissan GT-R and I'm looking to increase its horsepower. I've heard about various modifications such as ECU tuning, upgraded turbos, and exhaust systems. What would be the most effective and reliable way to increase the horsepower of my GT-R?

Based on my personal experience, ECU tuning and upgraded turbos are the best modifications for increasing the horsepower of a Nissan GT-R. These modifications will provide the most significant gains in power without risking the reliability of your engine.

I would recommend getting an exhaust system that is specifically designed for the Nissan GT-R. This will not only increase horsepower, but also improve the overall sound and performance of your car.