different, the skyline GTR uses the RB26DET (2.6 inline 6) and the 350z uses a 3.5 v6 (not sure of engine code) iirc there are turbo kits for the 350z but im not too clued up on this.
id keep the rx7 if i was you, looks way better than the z! spend your money on getting mega power from the rx7 (and frequent rebuilds

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