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z6 swap to a 90 civic si

Discussion in 'Civic and CRX - EF' started by Chavezcraz, Apr 1, 2010.

  1. Chavezcraz

    Chavezcraz got bseries?

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    Ok. I'm not 100% new to the game but i'm new to doing it with no supervision. My last 91 si got a b18 slapped in it. I remember beating the firewall in and a few things with the wiring harness and such. But my main reason for posting here is in regards to a d16z6 swap.

    See how i'm now earning the main income for the house i'm trying to keep this within range of "my" free money. : ) So i found a 90 si hatch already lowered and with a invidia exhaust, it is primered and a super clean interior. Immediately wanted the car...

    [​IMG]

    Gave 350 for it and he even threw in a p28 ecu with a d16z6 wiring harness converter(150 dollar value here in south west ohio). Now this sparked my interested in the Z6 conversion. I found a Z6 full drop out from a 94 civic ex, the engine has a knock but was still drivable to his home when the knock started, so he didn't have full engine failure. He told me 250 bucks for the full dropout including all mounts, head, intake, block, tranny,dizzy, flywheel clutch, wiring harness, motor mounts all that good stuff. So for 250 for everything i figured i'd take a risk and see if i can simply find the issue and correct without buying a rebuild kit. So i've read a million posts and seen a million pics. I guess i'm just looking for specific answers to my questions. Here we go.

    1.) With the p28 ecu and wire harness conversion kit will i need to change any wiring inside the car? Or will the conversion kit take care of all that? I ask because the kit he gave me with the ECU have a few wires hanging off of it coming out of each wiring juncton on the ecu.
    [​IMG]


    2.) The tranny i'm getting with eh z6 is hyrdo of course : (. My si is cable and i wanted no part in switching it... haha. So i found a 91 si 5 speed cable tranny with clutch and starter for 70 bucks. Don't do a ton of highway driving so i thought the sporty 5th gear would be a good pick for me. Will this tranny work?


    3.) I have read and saw many people talking about cutting this plug and lengthening this plug to the point where i felt so uneducated i was ready to stop the swap. haha. Now with the Z6 harness coming from all the sensors, injectors, dizzy, alt and all the good stuff on the engine.... Will i need to do any cabling altercations under the hood? I have heard that i'll need a 4 plug 02 sensor, and to extend the MAP sensor. Keep in mind i'm from OHIO and we have no emissions anymore. So what will i for sure have to mod under the hood?


    4.) With the Z6 engine harness, will i be able to plug directly into the existing SI harness under the hood?
    [​IMG]
    5.) With the Z6 header, will it be in the same placement as the 90 SI header? So will i able to use the after market exhaust which came with the stock engine that was pulled out?


    6.) Will the axles from the stock SI work with the Z6. I'm pretty sure they will seeing how i'm getting a 91 si tranny.


    7.) Will the Vtec work using the Z6 wiring harness?(assuming i can just plug it into the SI harness and use the conversion plugs that the guy gave me with the p28ecu)


    8.) Will the stock 90 SI radiator work with the Z6.


    9.) Is there anything that i'm missing? I already have the shell, and i'm picking up the engine Z6 engine and the 91 si tranny this weekend so i want to be ready.

    10.) I have also heard that i need the stock motor mount for the driver's side for the swap. Is this true.(i have it just want to make sure that i need to use it).


    I've read that the swap is easy with the right parts and wiring. Do i have all the right stuff to make this work? If there is anything you guys can add to help me through this i'd greatly appreciate it. I know you are all very knowledgeable and i hope this is a smooth process for me. Thank so much for any help/advice. More pics to come also when i start.
     
  2. Chavezcraz

    Chavezcraz got bseries?

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    P.S. What are those wires hanging off the ecu conversion harness for? the ODB plug?
     
  3. ANGDAN001

    ANGDAN001 New Member

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    good swap im going to do the same swap! dont know if i have time this weekend though.. use stock 90 si wiring harness just use ecu jumper and distributor jumper also ull need to do wiring for vtec
     
  4. Chavezcraz

    Chavezcraz got bseries?

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    So i'll just have to plug the p28 into the stock wiring using the converter i have. So i have to wire the vtec straight from the ecu?
     
  5. Chavezcraz

    Chavezcraz got bseries?

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    Ok so the wires that are loose on the conversion wire harness i have are for the dizzy,vtec,and 4 wire 02 sensor right? So everything else is good to go? No need to extend anything?

    And i'll only need the driver's side motor mount. I can use the 90 si axles and everything. Have i finally mentally figured this out? haha
     
  6. CAFROG

    CAFROG Honda Minion VIP

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    I think you got it.....try it out and make a thread on it so others will gain from your experience later on down the road
     
  7. Chavezcraz

    Chavezcraz got bseries?

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    Will do. Plan on taking pictures throughout the process and writing up a noob friendly how to.
     
  8. Chavezcraz

    Chavezcraz got bseries?

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    New Pics
    [​IMG]
    [​IMG]
    The seemingly last si tranny in ohio it appears... haha
    [​IMG]
    [​IMG]
    My Buddies SR20 nissan engine we picked up the same day.
    [​IMG]
     
  9. Chavezcraz

    Chavezcraz got bseries?

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    New Pics!

    Doubled up a pick at the end, this is my engine and my buddies sr20 nissan dropout
    [​IMG]
    Red Top Baby
    [​IMG]
    Intercooler
    [​IMG]
     
  10. D16SiHatch

    D16SiHatch New Member

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    plug the obd0 to obd1 ecu jumper into your stock cabin harness and that will allow you to then plug in the p28. the extra wires at the subharness are for the 4 wire o2, vtec pressure switch, and vtec solenoid. you will also need a dizzy adapter so that you can connect your obd1 distributor to the obd0 harness. you could cut off the old connectors and solder on the new ones, but i'd recommend not cutting up your stock harness. let me reiterate, you will NOT be using the obd1 z6 harness.

    the si cable tranny will be fine, and your stock axles are what you need to use. so your good to go there. your old exhaust will bolt up the z6 with no problem, and the stock radiator will work just fine with the z6. it is true that you need to use the stock engines post mount and motor mount.

    only thing i can think of that you haven't mentioned is that you'll need to extend the coolant fan switch wiring. on your old engine the switch is located on the back of the block. it looks like this..

    [​IMG]

    and you will see wires back there like this

    [​IMG]

    extend them and connect them to the new switch on the z6 which is located on the thermostat housing. if you don't connect this, your radiator fan will not come on.

    [​IMG]
     
  11. Chavezcraz

    Chavezcraz got bseries?

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    Turbo?

    Perfect. Thank you D16SiHatch. I remember reading that about the fan switch. Starting this friday we are putting the Z6 on the engine stand and seeing where the knock is coming from. Hopefully it's an easy fix (main bearings). Then gonna throw er in the EF. The tranny was bought already pulled out so hopefully no grinds or anything. In total have 600 in the car with about 300 left over. I still need a battery and odds and ends. I'm going to go with the homemade turbo idea. Wanting to push about 5psi or so since i'm not going to rebuild the block if i don't have to. I made an account on DSMsource.com but am unable to view the listings yet. What vehicle should i look for a turbo off of? Any ideas?
     
  12. D16SiHatch

    D16SiHatch New Member

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    off the top of my head i cant think of what stock turbo's you might be able to use. i think there are some, but hell if i can remember them lol. the problem is most times the flanges are proprietary to a given vehicle and trying to make them work on a generic t3/t4 flanged manifold is kinda squirly.

    as far as the knock sound, i really hope for your sake that it was caught early enough. because if not and the crank is scored, you will need to find a new one. and grinding off the stock nitride coating and running oversized bearings does not usually end well.
     
  13. Chavezcraz

    Chavezcraz got bseries?

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    Yeah. The guy i got the z6 off of seems to be legit and honest. He pulled the entire engine out in 45 minutes with only hand tools and a oem jack from the car. haha. i have talked to him several times over the last week in regards to ways of doing the swap. But like you said i really hope crank is in good shape for my own sake, i can get another z6 block for 50 bucks if need be. Thanks for all the info everyone. Been looking hard at doing a turbo before the engine is even in the car and running/moving.
    Am i able to run 5psi without doing too much changing? I've heard i will need new injectors (any idea what size? i've hear anywhere from 300cc to 550cc) and i'll need a new mass air flow sensor (any idea off what vehicle i'll need?) and a new fuel pump(can i get this from another car? can i do inline?) and will i need to tune my car if i only run 5psi? I'm on a budget right now so my realistic plans are get the motor in the car and running. Basically i'm asking if i boost my car with an oem turbo from another vehicle and only run 5psi what all do i absolutely have to upgrade. Thanks again.
     
  14. D16SiHatch

    D16SiHatch New Member

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    to even run 5psi you will need bigger injectors than stock. most people go with 440cc's when running a small amount of boost and keeping power goals below 300hp. our cars don't have maf sensors, they have map sensors (manifold absolute pressure). the stock one is good to about 10psi safely, so you'll be fine there. on these cars you pretty much always do an intank pump. the common one used is a walbro 255 lph pump. you can pick one up for about $100. and the biggest expense is going to be the tune, which is an absolute necessity. depending on what your options are with local shops you might be able to get a chipped ecu and have them tune that, or you might have to get a hondata system. i know the place near me requires at the least the honda s100 because they don't tune with crome, neptune, etc.
     
  15. Chavezcraz

    Chavezcraz got bseries?

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    Gotcha, ok yeah tuning seems to be a huge chunk of the turbo budget i'm seeing. I've heard nothing but raves about crome and hondata. I have started lookin at what i need to do to chip/socket? my ecu. I work as a computer tech for Kohl's so i'm not new to soldering or anything curcuitry related. So i feel comfortable with any mods i may have to do. Should i check with a local tuner or is it really difficult to do myself? Also if i decided to go with hondata or crome are the chipping requirements different? Or can i chip it and the inputs/outputs will work with either programming system? Sorry for all the continual questions. I appreciate your interest!
     
  16. D16SiHatch

    D16SiHatch New Member

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  17. Chavezcraz

    Chavezcraz got bseries?

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    Do i have to remove the injector resistor box also for this engine?
     
  18. D16SiHatch

    D16SiHatch New Member

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    if you use obd1 or obd2 injectors then yes, otherwise no.
     
  19. Chavezcraz

    Chavezcraz got bseries?

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    Decided to go with a b18a1 from a 91 teg. Used to have the same setup in an old civic and loved it.
     
  20. austinav10

    austinav10 New Member

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    hey sup guys I know that this post has't been updated for awhile but I need some help on my jumper harness. I already did the swap on my ef with a z6 motor. I have jumper harness for ecu and dizzy. On my jumper harness it is already plug in, but I have one white single wire from my ecu jumper that I have no idea where it goes.
    ok here I have a unknown jumper harness, there are four adapter that are already wire from the ecu jumper harness( all the lose wire been hook up to all four adapter)
    1 adapter to the vteck.
    2 adapter to the vteck oil pressure
    3 adapter to a four o2 sensor
    4 adapter? Its a white single wire
    Where does this white wire go to?
    Thanks
     
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