I want to know which of the following mods would get me the most power.....headers, pulleys, or y-pipe/test pipes?

 

SEARCH!!!

 

None, save up for Twins.

 

There's a lot of info already out there, but IMO, lightweight pulleys would free up the most power. Make sure you go for lightweight and not underdrive pulleys...big difference.

 

https://my350z.com/forum/engine-and-drivetrain/254527-unorthodox-pulleys.html

 

What are your long term plans powerwise? If you plan on going FI, then some of those parts might not be compatible with some of the kits. Out of those listed, test pipes would be the bast bang for the buck. It gives you a little power, and some good sound, and its relatively cheap. Pulleys are also a great bang for the buck.

 

well if you can afford headers then you can afford both the pullies and TP, which should net you more than headers. Plus, install on TP/pullies will be about have the cost of installing headers.