1990 to ‘94 300ZXs suffers from an inherent design flaw of the fuel injectors. Nissan used a uniquely designed wet coil type injector back then that left the injector coil wire exposed to chemical attack from oxidizers added to gasoline as years went on. To compound the problem, Nissan designed the injector electrical circuit so the 12V+ side was hot all the time, even when you are in bed sleeping! Once the injector coil insulation has started to deteriorate, a small amount of current can flow across the fuel, eventually shorting the injector coil or in many cases, cause an open circuit in the injector, either way, you end up with dead injectors. The late style injectors used from 1995 don’t have this issue (Nissan also fixed the 12V+ problem with a switched supply on the later cars). So if you plan on growing old with an early Z32, you will want to convert to the late style injectors and this kit is the least painful way to do it! There are other solutions and other adaptors, but this kit provides the lowest profile top clamp available, for easy access without pulling the upper manifold. Other adaptor designs leave a significant void around the lower nozzle, causing fuel to accumulate and drip at idle, not so conducive to a smooth idle! Our lower adaptor specifically addresses this by filling in the void between the injector and the fuel rail. Kit includes 6 upper and lower adaptors, bolts, and lower adaptor O-rings. Various sized late injectors, ECU calibrations, and electrical connectors are also in stock.