ZC Swap FAQ


What is a ZC Motor?
Does it Bolt in?
What Transmission do I have to use?
What are the Wiring Changes?
What ECU do I use?
What do I use for Parts?
Which Headers Fit?
Which Axles do I use on the ZC Tranny?

WHAT IS A ZC MOTOR?
        The ZC motor was available in Japan on EF Honda Civic Si Models.  Dual Overhead Camshafts and 9.5:1 compression make around 130 Horsepower From 1.6 liters of displacement. There is a brown covered DOHC ZC that fits 86-87 integras, and a black covered DOHC ZC from the 88-89 integra, but the main focus of this FAQ is the Black ZC motor for EF(88-91) series Honda Civics. You can identify the civic ZC by the valve cover mounting. On integras, the cover mounts in the center, on the civic it mounts by the edges.
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DOES IT BOLT IN?
         Yes. The ZC motor came from the same kind of car as yours, and will bolt in with no problems, the only changes to your car will be in the wiring.
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WHAT TRANSMISSION DO I HAVE TO USE?
        
You can use any USA spec EF civic Transmission, 5spd, 4spd, HF, Si, or Automatic. Also available is the ZC tranny from Japan. The ZC tranny is a strong unit and works very well, it is very similar to the 86-89 Integra Transmission. The ZC tranny uses Equal length axles and an intermediate shaft to reduce torque steer. You can use the stock tranny and axles with the ZC for the easiest swap, or import yourself a ZC tranny for the ultimate in steering control. ZC transmissions have been reported to leak small amounts of transmission oil at the inner axle seals. Also, for the truely ultimate Tranny, check out your options on the ZC/Si Hybrid Tranny Page. Click Here To Compare your gear ratios to other trannys.
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WHAT ARE THE WIRING CHANGES?
          Wiring diagrams and information on how to wire your ZC motor can be found on the ZC wiring page.
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WHAT ECU DO I USE?
          You have several options for ECUs. The factory Si Computer will work, but the rev limit is way to low to see the potential of the ZC. Many people are importing ZC ECUs from japan, and these work very well. Most people find it is best to run a 88-89 integra ECU. These are not as hard to locate as ZC ECUs, but will give you very good performance. If you have an Si, You could use the stock computer and have somebody perform a chip upgrade on it, to raise the limiter and remap the fuel. many companies will not modify 88-89 integra ECUs. All the above ECUs will plug into your factory wiring harness. Even if someone on some message board says it will, The Integra board will not fit into the civic case in any fashion that ZCspeed would consider safe or smart. The integra board is about 4mm wider than the civic, and the heat sinks will not touch the walls like they should. We recommend, however, drilling a hole in the top of your Integra ECU so you can see the Check engine LED without moving the computer or using mirrors.
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WHAT DO I USE FOR PARTS?
         Timing Belt: 88 Honda Prelude Si p/n - 14400-PK2-004
         Distributor cap: 88 Acura Interga p/n - 30102-PM7-305
         Rotor: 88 Acura Integra p/n - 30103-PM5-A05
         Head Gasket: 88 Acura Integra
         Intake Gasket: 88 Acura Integra p/n 17105-PG6-S00
         Exhaust Gasket: 88 Acura Integra p/n 18110-PG6-003
         Water Pump: 88-91 CRX/Civic
         Oil Filter: 88 Acura Integra p/n 15400-PR3-004   
         Spark plugs: NGK BCPR6E-11
         Oil pan gasket: 89 Integra
         Spark plug wires: 89 Integra
         Throttle Body: 88-91 Civic/CRX Si or 88-89 Integra
         Valve Cover Gasket: 88 Acura Integra
         
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WHAT HEADERS FIT?
        The bolt pattern for 88-91 civic Si is the same as the ZC, but the ports are shifted about 3mm. You can port the header flange with a die grinder and this works just fine. The 88-89 Integra header fits the bolts and the ports, but I havent tried to fit the integra header to the civic exhaust (have you?).  
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WHICH AXLES DO I USE ON THE ZC TRANNY?
        Many people have reported using 90-93 integra axles with no problems, however, ZCspeed recommends a 90-93 integra left axle with a 1985 Honda Accord SE-i 5spd Right axle. The Accord axle is one-half inch longer than the integra axle, eliminating problems with the axle coming apart when the wheel is turned all the way to the right. The accord axle isn't very easy to find, but we get them from time to time. Some people have reported making custom axles with various civic/integra parts.
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