s14 De swap into 89 SOHC

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cd1921
Posts: 2003
Joined: Mon Jul 19, 2004 11:40 am
Car: 91 Black 240sx. Tein S springs. Gr2 KYBs shocks. 17" wheels. JDM Folding mirrow. Injen CAI

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I have some question, i bought my 89 s13. with a broken timing chain, but looks like there is more then just that.I have someone selling me a s14 (95-98) engine, with ecu, wireharness. and all sensor. First off can i use my stock transmission?What would i need to make this work in my 89 s13. is there a wiring diagram to what needs to be connected too.

Thanks for any help or suggestions.


dareo
Posts: 892
Joined: Thu Jul 17, 2003 10:13 am
Car: 1993 Q45, 1989 240sx

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I have heard that the E transmission will line up with an S14 trans, correct me if i'm wrong. You will need to change the engine harness, ecu, probably powersteering setup, and tach. And probably a couple things i'm forgetting.

Depending on how much your getting the KA for, consider a Venus RB20 front clip just to get you by for a while. 1200 bucks and you can be boosted and running around again.

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cd1921
Posts: 2003
Joined: Mon Jul 19, 2004 11:40 am
Car: 91 Black 240sx. Tein S springs. Gr2 KYBs shocks. 17" wheels. JDM Folding mirrow. Injen CAI

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well i can get the KA engine with harness, ecu, PS pump, AC compressor. For 600 bucks off a 97 s14 with 70,000 miles.

Thats why i wanna know how much work is involved, since the engine its an OBDII..

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Philsnotfalling
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Joined: Mon Oct 27, 2003 3:18 pm
Car: 90 hatch 93 coupe
Location: conroe, tx

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you're in luck I've been researching this for a year lol still not done. there used to be a good thread about it but I can't find it no more since nico moved.

power steering lines must be changed out with a s13 dohc set up.

air intake will not line up with the throttle body after market for the dohc s13 will work.

I'm not sure about the a/c compressor yet.

yes transmission will work.

91-94 exhaust mainfold I'm not sure about but I went with a 91-94 hotshot header. blocking off egr stuff.

electrical... I sent my sohc wiring harness and the dohc wiring harness with 95 computer to mckinney to have the service done. $320 bucks but its aplug and play type a deal. use the same secondary harness to the transmission and starter and stuff. I should prolly check with mckinney if my old tach will work... hmmm. I bought a 91-94 gauge cluster anyway.

sutff I'm doing while everything is out...energy suspension bushing kittein tie rods and new nissan bootshotshot headernew timing chainsthermostatspark plugs, b/c you need engine out of the carintake cleaned by machine shopflywheel turnedcenterforce dual friction clutchthrow out bearingauto-5spd conversionnew front main and alot of other gasketshad the valve cover smoothed and paintedair intakekoyo aluminum radiatorflex alite fansnismo motor mounts and transmission mount

I think thats it I dunno I have like 4-5 gs already into the project should have the engine in the car next week. and the wiring harness back in 2-3 weeks(just sent out last night). I also bought two service manuals but came out with three 89, 91, and a 95.

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popogto
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Joined: Fri May 14, 2004 5:55 am

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my car is at the shop doing the same thing now, and for the ac compressor, i heard theres some repiping to be done.

Buforian
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Joined: Wed Sep 15, 2004 5:58 pm
Car: 90 240sx

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Philsnotfalling
Posts: 209
Joined: Mon Oct 27, 2003 3:18 pm
Car: 90 hatch 93 coupe
Location: conroe, tx

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ahhhh that thread is for a s13 dohc into a sohc car.... I thought the wiring was alittle bit more complicated than that going s14 into s13.... the colors on the wires don't match at all where this thread said it did. I'm swaping an entire 95 ka into my 90 so it will "behave" like a 95 completely... no external coil for me no extra egr stuff either.

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cd1921
Posts: 2003
Joined: Mon Jul 19, 2004 11:40 am
Car: 91 Black 240sx. Tein S springs. Gr2 KYBs shocks. 17" wheels. JDM Folding mirrow. Injen CAI

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thanks to all the replies, but besides the wiring harness, Is there anything else that i need to worry about since the 96+ are OBDII and my 89 SOHC isnt???

Thanks for the help again

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Twinchy
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Joined: Wed Feb 18, 2004 10:09 am
Car: Peg leggin 240sx

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i have a 90 coupe and i am planning on doing the de swap too. if i were to buy those clusters on ebay (the jdm clusters) can i just take out the rpm tach and replace it with my old one on my cluster?

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frapjap
Posts: 13175
Joined: Thu Jul 01, 2004 2:46 pm
Car: '99 Pontiac Firebird Trans Am
'07 Subaru Legacy
Location: South Coast Massachusetts

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I made the write up for the swap. Its what you're looking for. Its titled, "SWAP! ka24e to ka24de" Its got about everything you'll need and some trouble shooting.

BomexS13
Posts: 2561
Joined: Fri Dec 19, 2003 8:36 pm
Car: '89 Nissan 240SX
'00 Toyota Celica

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Mines an 89 with a 95 DE as well:)

gumby
Posts: 994
Joined: Wed Oct 15, 2003 6:53 pm
Car: '89 240sx sohc

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didnt have to do this myself, but i saved the following posts. hope theres some useful info in there:

95 DOHC into 90

Mechanically it all bolts up no problems.Here are the main differences:

Mechanical:Power steering - different between SOHC (pass. side) and DOHC (driver side). To swap, you need the DOHC power steering lines, reservoir, and hoses.Intake - different shape, so can't swap thatThrottle cable - SOHC too short to reach DOHC throttle body best to get a DOHC cable.A/C is a different compressor entirely, though in about the same position. To make a DOHC compressor work with a SOHC system, you'll need to have a specialty shop custom fit the DOHC lines to your SOHC system. No, the DOHC lines do not just bolt to the firewall fittings, they are different sizes. Also, SOHC systems used R12 refrigerant, now illegal. You'll need to convert to R134, which means a system flush and new drier.Ignition - I understand the '91-'94(?) sytems use a different coil, but not entirely sure. The '95+ systems don't have an external coil, so not an issue there.

Electrical - SOHC systems and DOHC systems are somewhat different in the wire routing, primarily the power/fuse wiring for the ECU (at least for the '95 vs '90 systems), but also some sensors and inputs for the OBD, tach, speedo. It's not really a big deal if 1) you have the FSM (wiring diagrams) for both the SOHC and donor DOHC systems, and 2) you can read and understand the wiring diagrams. Then its a matter of identifying the differences, and cutting/splicing the DOHC harness to match the SOHC systems. The harness plugs that connect to the engine room and dashboard harnesses are different, so you have to cut to SOHC plugs and splice them into the DOHC harness. Takes a little time and you have to do it right, but like I said, not bad if you have a bit of understanding about how electrical systems work.

Also, you need a DOHC tach as the SOHC tach will not work.

Obviously you also need the DOHC computer.

You may have to change the transmission harness a bit to make it mate up, but that's minor (for the '95, I had to wire in the 2nd O2 sensor and crankshaft position sensor, no big deal).



Wiring:MUST use end of SOHC harness and sauter respective lines to the DOHC wiring harness from the engine to the dash/gauges. Yellow / Red stripe Tachometer signal

Yellow / Green stripe Speedometer signal

Orange Ignition start

Black Ground

Blue / Green stripe AC signal

Blue / Black stripe Water temp signal

I left the gauge cluster cover how to swap a S13 DOHC motor into a SOHC equipped S13, as well as parts necessary.

1. Source parts needed for swap (full parts list is at bottom of post).2. Ensure you have adequate tools, space, equipment, time and money to accomplish this.3. Source a motorset.4. Yoink old motor from chassis. You can unbolt the motor mounts from above or below. Guide the motor out, making sure it doesn't damage anything on it's way out. I'd pull the transmission at the same time as well, in case you're going to be utilizing the same transmission ,so that reinstallation will be much easier.5. Remove A/C lines. You will have to get custom lines made if you want to keep A/C, or make a custom bracket for your SOHC compressor.6. [OPTIONAL] Remove any other engine bay items like AIV, airbox, etc. and prepare engine bay to your liking. (clean, sand, paint, nothing, etc)7. Move SOHC power steering lines over to driver's side & install DOHC power steering reservoir -OR- install S13 DOHC power steering lines.8. Replace SOHC throttle cable with DOHC throttle cable. Two bolts at the firewall behind the accelerator (and remove the accelerator to make life easier.9. Pull SOHC engine harness. You can either cut it at the firewall, leave it intact and pull it thru the firewall (into the engine bay), or whatever is easiest for you. Don't throw it away just yet - you may want extra wiring, or to keep the connectors for future use.10. Install DOHC engine harness. Reverse of above. 11. If you're doing a manual swap, NOW is the time to drill out the place for the clutch master cylinder, install it, and run the hardline down.12. reinstall everything you took out to prep the engine bay, like AIV, airbox, cruise control, etc.13. Prepare your new motor. This means whatever maintenance you'd like to perform on it before it goes in, i.e. water pump, vacuum line replacement, thermostat, reseal oil pan, timing chain job, belts, etc. It's about 11ty billion times easier working on an engine when it's OUTSIDE of a car.14. Slide your slick new DOHC KA into it's new home. Again, watch your clearances. You don't want to damage anything or scratch that fresh new paint, right? Make sure you attach your heater hoses during this step. It'll make life MUCH easier.15. After getting the transmission mount in and bolted down, tighten down the motor mounts. This is important, as your engine can sit cockeyed and still be tightened down at the motor mounts.16. You're getting close! Reinstall your clutch fan (or not if you have electric stuff), and install your radiator and fan shroud. Install your Upper and Lower radiator hoses at this time.17. Start connecting the harness to the motor. Now is the time to do a clean job of installing the wiring.18. Finish installing everything else, like intake piping, sparkplug wires, etc.19. Your engine bay SHOULD be complete. Now it's time to address swap wiring.

Wiring:F'ing SIMPLE.1. Locate the body harness (under dash harness that attached to the ECU) that attached to your old harness. Cut the old connector off (the one that attached to your SOHC harness) and attach your DOHC body harness connector. Just match the colors! There will be some wires left over. These are for the SOHC's diagnostic plug, and are unnecessary. Please note: Your car will NOT be able to hook up to a CONSULT tool. To accomplish this, you must get a body harness with all the correct DOHC wiring. This is why we cut the body harness connector off, and not the engine harness connector.2. I recommend using a soldering iron, shrink tubing and electrical tape as opposed to butt connectors. It makes for a much cleaner job, and a cleaner electrical signal.3. You need to swap out your tach if you want one that works. No wiring is involved, but it must be done. Simply pull your combination meter (gauge cluster) and remove the three screws behind the tach. Lift and separate. Installation is reverse of removal.4. You should also extend the wires that go to the PS line sensor and connect that to your subharness. It's not necessary, but it's a good idea.

Parts needed:S13 DOHC KA (or S14 KA with OBDI lower intake plenum, S13 DOHC distributor and S13 DOHC coil & others)S13 DOHC engine harness & body harness connector.S13 DOHC MAF, intake piping, coil, tachometer, power steering reservoir and hoses (low pressure), throttle cable (and cruise cable if you have it.), engine-side brake booster vacuum hose, engine/transmission subharness (if swapping from automagic).Optional: S13 DOHC power steering high pressure lines

A few sidenotes: S13 AIV system is same/same. Nothing needs changing there. For cruise control, the cable length is dependent on the motor. DOHC cruise control can't use the SOHC cable without a weird custom bracket.

For my swap, I used a '95 KA, adjusted to behave like a '92. I used a '92 exhaust manifold, EGR tube, distributor, lower intake plenum, coil, and vacuum routing. To eliminate the secondary butterfly vacuum line, I pinched it and sealed it. I performed a fully stock swap. No EGR or AIV elimination, no intake or cams or otherwise.


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