A tune is totally worth it. It will help you maximize the performance of your bolt-ons as well as get rid of that shitty stock tune throttle lag. A tune can also add features like launch control and such.
It may not be absolutely necessary after installing exhaust and/or intakes. But there are benefits for sure.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |