Engine is identical. 2009, as the first model year, has a few more kinks that were worked out in the later models. I would look for 2011 or later. 2013 or later if you prefer the newer wheels and front bumper. If you are so inclined, with a little bit of research, you should be able to find all the minor differences in each model year (like the 2012 model introduced a small water-based oil cooler).
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |