There are actually a couple of different things going on with the 2015+ model years. But the fact is any power difference between the models is essentially negligible. The weather variable can impact your dyno results far more than these minor design changes that have occurred over the years.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |