what ZC are you getting? the ZC that bolts into and works with the 1g CRX (3g Civic) is the "brown top" JDM DOHC ZC from 86-87 JDM Integra (basically same as USDM 86-87 Integra) which uses the 86-89 Integra transmission, axles, knuckles/hubs, shift linkage and ECU - it has vacuum advance ignition which is compatible with the 1g CRX Si - most of the wiring plugs right in - there is also a "black top" JDM DOHC ZC from 88-89 Integra that is basically the same as the D16A1 from the USDM 88-89 Integra and has the electronic ignition advance - it will bolt into 1g CRX using 86-89 Integra transmission, etc., but requires considerable wiring - there is the "black top" JDM DOHC ZC from the 88-91 JDM Civic/CRX Si which bolts into the 2d gen CRX (4g Civic) and uses the 88-91 Civic/CRX L3 transmission - this engine is not the same as any other Honda engine, USDM or JDM, and will not bolt directly into 1g CRX (3g Civic) - there is the "black top" JDM DOHC ZC from various 92-up JDM cars which is similar to the "black top" for 88-91 models, but is OBD1 and has different front mount - will bolt to any 92-00 D-series CRX/Civic transmission - will not bolt directly into 1g CRX (3g Civic)
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