The real deal would be a solution that doesn't cause the cylinder pressure to spike. Like Rusty said, a simple ignition cut is all you need. But there are also stand-alone ECUs, like the Motec one Elmo mentions, that will do it properly.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |