The 2009 refresh (NC2) gave the LF-VE a stronger bottom end and, on many cars, a factory oil cooler. If you plan to rev it hard or track it, an NC2/NC3 6-speed is the engine to start with.
The early NC1 engine is durable but built to a milder spec. For 2009 Mazda revised the internals to support a higher redline on the 6-speed cars.
What changed at NC2
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