ZC DOHC for an 89 RT4WD any benefit to different years

woodiwoodi Wagonist
in Engine & Drivetrain
I've found a few ZC DOHC motors to swap into my 89 RT4WD and was wondering if there was any benefit to getting an 88-91 version vs a 92-95 version. The two motors I'm looking at right now are
88-91
92-95
I'm open to getting a motor from pretty much anywhere but that place is the closest with the best price I've found so I can just go pick the engine up rather than paying shipping.

From what I've read elsewhere it seems like either of these should just bolt up but the later model might need an adapter for the ecu? The items are listed as including the ecu so does that still hold true.

This is gonna be my first motor swap so I'm trying to get everything as close to fitting right off as possibly to reduce a little bit of the pain down the road. Thanks all.

Comments

  • evol911evol911 familEE
    88-91 is the one you want. 92-95 is obd-1 and won't work unless you rewire some things. 88-91 is a drop in besides a distributor harness that has to be changed.
  • CharbCharb Administrator
    evol911 wrote:
    besides a distributor harness that has to be changed.

    Watch how many beers you drink before you do this. I know this was my biggest problem lol

    Other than that it's pretty straight forward.
  • woodiwoodi Wagonist
    Is there a special harness that needs to be bought to hook up the distributor or just some cutting and splicing per a write-up I can find online somewhere?

    In addition I've been trying to search but does anyone know of any good write ups that cover the whole process. This being my first swap any guides/tips or info can really help. Is there anything particular to the RT4WD that I might miss from reading non RT4WD stuff.
  • CharbCharb Administrator
    Google is your friend for wiring. I got my wiring diagram years ago from a ZC forum.

    Depending on where you buy your motor, it will come with the Japanese harness. We just de-pinned the stock dizzy plugs from the A6 harness, and re-pinned them with the Japanese dizzy plug. One had two plugs, the other has one plug. Can't remember which had which. Easy and not janky. But you could splice if you're ok with that sort of thing. Solder it and do it right if you do. Don't use butt connectors.

    But ya, make sure you buy an 88-91. That will be the only wiring you need to do.
  • evol911evol911 familEE
    You can find the harness on EBAY sometimes...

    Please search!!!! I know I've already posted this info so many times on this forum....
  • woodiwoodi Wagonist
    Thanks for the help. Sorry about the repeat questions. Did do some searching and reading around before posting but guess not enough.
  • SikocivicSikocivic Wagonist
    These guys can give you all the info you need on those motors;

    http://www.thezcr.com/
  • HaydzHaydz Moderator
    If you use the DOHC ZC motor with its standard harness and dizzy then there is no wiring needed, it's literally plug and play.

    It's just like lego, get the bits and go nuts you can't mess it up, easiest swap in the world.
  • CharbCharb Administrator
    Sikocivic wrote:
    These guys can give you all the info you need on those motors;

    http://www.thezcr.com/

    That's the one I used!

    Haydz wrote:
    If you use the DOHC ZC motor with its standard harness and dizzy then there is no wiring needed, it's literally plug and play.

    We actually did this. Except all of the bolt mounting holes don't line up. I think 2/3 if I remember right.
  • swaiteswaite New Wagonist
    http://cgi.ebay.com/ebaymotors/88-91-Ho ... ccessories
    This is the distributor adapter you will want to get. I have no idea who this guy is but he is awesome.
  • CharbCharb Administrator
    swaite wrote:
    http://cgi.ebay.com/ebaymotors/88-91-Honda-Civic-Crx-DOHC-ZC-Distributor-Adapter-OBD0_W0QQcmdZViewItemQQhashZitem3efc79367dQQitemZ270523774589QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
    This is the distributor adapter you will want to get. I have no idea who this guy is but he is awesome.

    Save your money and re-pin it yourself
  • evol911evol911 familEE
    swaite wrote:
    http://cgi.ebay.com/ebaymotors/88-91-Honda-Civic-Crx-DOHC-ZC-Distributor-Adapter-OBD0_W0QQcmdZViewItemQQhashZitem3efc79367dQQitemZ270523774589QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
    This is the distributor adapter you will want to get. I have no idea who this guy is but he is awesome.


    ^ x2!!!!!! Thats the one you need. Thanks Skyler, I couldn't find it on EBAY when I was looking for it.
  • CharbCharb Administrator
    evol911 wrote:
    swaite wrote:
    http://cgi.ebay.com/ebaymotors/88-91-Honda-Civic-Crx-DOHC-ZC-Distributor-Adapter-OBD0_W0QQcmdZViewItemQQhashZitem3efc79367dQQitemZ270523774589QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
    This is the distributor adapter you will want to get. I have no idea who this guy is but he is awesome.


    ^ x2!!!!!! Thats the one you need. Thanks Skyler, I couldn't find it on EBAY when I was looking for it.

    Did you not get a JDM harness with your ZC? Seems like a waste of 15 bucks to me
  • woodiwoodi Wagonist
    Haydz wrote:
    If you use the DOHC ZC motor with its standard harness and dizzy then there is no wiring needed, it's literally plug and play.

    It's just like lego, get the bits and go nuts you can't mess it up, easiest swap in the world.

    That's what I like to hear. Though do I need to modify my lego's a bit? I was reading on an old thread of yours that the zc exhaust manifold won't fit. I gotta use the one from my old motor and grind the ports to match. Is that right?

    Also do I need to pull the transmission with the motor or can I leave it in the car and just pull the engine by itself? Everything I've read thus far has been for FWD and tells you to take it all as one unit. If I do need to pull the transmission is there more steps other than pulling the front drive shafts that are necessary since it's an RT4WD transmission?

    Thanks again for the help. A good community of people who know what there doing can really help to take some of the headache out of this stuff..
  • HaydzHaydz Moderator
    You can either use your stock one with the ports ground out or...

    Use the top half of the DOHC ZC header and the bottom half of the SOHC ZC header, they will bolt together fine, clear the ports fine and also clear the transfer case and sump. :)

    I would remove the engine and transmission as one unit in this case. If you were changing only the gearbox then i'd leave the engine in the bay, but to change the engine with the gearbox still in there would be incredibly awkward. In fact nearly impossible becaause of the crank pulley.
  • Eagle BeagleEagle Beagle familEE
    squeasy me...

    why you just start...
    shoot a lot of pics...

    some of you/US like that...

    I know I do...
    :shock:
  • jpoopoojpoopoo Wagonist
    so, basically if i have a sohc zc and wanted to drop in a dohc head, its plug n play? even from the first gen teg d16 head?
  • SikocivicSikocivic Wagonist
    jpoopoo wrote:
    so, basically if i have a sohc zc and wanted to drop in a dohc head, its plug n play? even from the first gen teg d16 head?

    No. The HEAD from the DOHC ZC will not fit on the SOHC ZC.

    Use the top half of the DOHC ZC exhaust HEADER and the bottom half of the SOHC ZC exhaust HEADER.
  • jpoopoojpoopoo Wagonist
    No. The HEAD from the DOHC ZC will not fit on the SOHC ZC.

    Use the top half of the DOHC ZC exhaust HEADER and the bottom half of the SOHC ZC exhaust HEADER.

    so it wont work? but whats the difference w/ the dohc zc top header and sohc zc header?
  • HaydzHaydz Moderator
    The exhaust ports on the SOHC and DOHC heads are aligned differently.
  • CharbCharb Administrator
    jpoopoo wrote:
    so, basically if i have a sohc zc and wanted to drop in a dohc head, its plug n play? even from the first gen teg d16 head?

    lol
  • woodiwoodi Wagonist
    Thanks for all the help. I'm still waiting for the girl I'm buying my wagon from to get the title from her parents so not starting anything soon but getting excited. Gotta make the trip to montreal in the next few weeks and pick up the motor. Probably take some time to make sure the motors in good shape (change timing belt and such) then start working on the swap once the weather warms a bit.

    Any ideas where to pickup just the sohc zc exhaust to get the lower half? Should the importer I'm getting the engine from have them? I couldn't find much on ebay.
  • SikocivicSikocivic Wagonist
    If the ZC motor you get has the exhaust manifold on it, just use that. All the ones I have seen come with both parts of the manifold or no manifold at all. If you don't get any exhaust with the motor, you can just pick up a stainless header on Ebay for $50 and grind the ports 3mm to match the motor. Its easy to see how to grind it. Just match the gasket to the header and you will see how much to grind.
  • HaydzHaydz Moderator
    Sikocivic wrote:
    If the ZC motor you get has the exhaust manifold on it, just use that.

    You cannot use the full DOHC ZC manifold on the RT4WD. It does not clear the sump and transfer case where the two pipes collect into one.
  • SikocivicSikocivic Wagonist
    Haydz wrote:
    Sikocivic wrote:
    If the ZC motor you get has the exhaust manifold on it, just use that.

    You cannot use the full DOHC ZC manifold on the RT4WD. It does not clear the sump and transfer case where the two pipes collect into one.

    I didn't see it was a 4WD. I guess I have to read better. :oops:
  • Eagle BeagleEagle Beagle familEE
    I didn't see...
    I didn't see...

    hey...!

    I'm begging for pictures here...

    :shock:
    jeezzz

    the humiliation...

    and my knee hurts..
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