92 ZC engine into a 90 civic SI HELP!!! Can it be

[kochease]

Hi, I have a 90 civic SI. I just bought a 92 civic DOHC ZC motor (just says ZC on block). The shop told me everything is the same as the 90-91 ZC's except the map sensor is electronic on top of the intake manifold. I started looking at my 90 si intake and it has more hoses. I was told is for the A/C idol. The 92 doesn't have this. Do you think a 92 zc can be swapped into a 90 civic SI? Does anyone know what hose #7 AND #12 are for on a 90 si?? I was thinking of leaving the map sensor disconnected on the 92 ZC.
CAN this swap be done?? I have a 91 zc distributer and cam sensor so my last issue is this intake.
What if I switch my engine wiring harness to a 92 SI?? I have a 92 ZC ECU and the distributer. Would this be eaisier???
Any help would be great
Thanks

 

[wiredjosh]

Yeah, I know it can be done because I had the same motor. It's a lot better than an 88-91, so consider yourself lucky! First, you'll want to lengthen the wires from the firewall-mounted MAP sensor and use the one on the throttle body, since the newer one will give better readings to your ECU. That eliminates one thing that you need to attach to your intake manifold. Then you just have to attach one hose for your purge cut solenoid, your brake booster (the great big one on the back...), your charcoal canister (this one can actually be omitted and just allowed to hang down towards the axle...) and that's really all you need to worry about. Your fuel pressure regulator has its own dedicated vacuum port, and if you have hoses you don't know what to do with, you can steal one of the ends off the old MAP sensor, use the "Y" fitting, get a little longer hose, and run it that way. If you have any problem hoses, snap a pic and email me at josh@wiredspeed.com and I'll try to help you out with it. Good luck!

 

[wiredjosh]

Oh, and I forgot to add that you should DEFINITELY NOT use the 92 harness. They have different plugs and totally different wiring arrangement due to the OBD1 shift at 1992. You can repin the Dist and make it work, but you will not be able to use the ECU unless you get an OBD0-OBD1 conversion harness. However, even if you do use the conversion harness, you cannot use the 92 engine harness. You must use the stock harness. The stock ECU in your car should run the motor fine. I do have a pr4 integra ECU that is OBD0 and that makes a big difference in the way the car runs for sale, if you're interested. Otherwise, don't worry about running that ECU.