93 240sx engine, 89 body?
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jjup_99
- Posts: 24
- Joined: Wed Jan 21, 2004 11:53 am
- Car: 1989 Nissan 240Sx Se
1994 Nissan 240Sx Convertible
93 240sx engine, 89 body?
I blew up my engine in my 89 nissian 240sx.purchased a 93 enginge, ecu, harness and transmission. Wonder if it will drop right in my car? anything special I have to worry about?
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hotshot240sx
- Posts: 141
- Joined: Sun Oct 27, 2002 2:30 pm
- Car: my 240sx
- Contact:
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hotshot240sx
- Posts: 141
- Joined: Sun Oct 27, 2002 2:30 pm
- Car: my 240sx
- Contact:
well i avoided this myself but heres what ive complied from 3 separate posts hope theres some useful info:
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 ****eyed 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.
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 ****eyed 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.