S13 SR20DET Installation
Into 1995 240sx
March 15, 2002
Installing a S13 SR20DET (red or blacktop) into a 1995 240sx is a very simple task that is not much more difficult than putting the same motor into a S13 chassis.
There are a few details that make this swap a bit different from swapping into the S13 chassis. The Upper Engine Harness on the S14 (KA and SR) has the plugs for your:
You will need to rewire all of the accessories that you have on your car to make them work with your engine and S13 SR20DET harness. If you are unfamiliar with S14's, you will also find the following differences from the S13
Everything bolts up to the S14 chassis. You will need to route one of your heater hoses to the bottom of the water cock valve so your heater will work properly.
*Note: I do not have ABS or CC on my car so I did not wire them up. It should not be difficult to do so however as you will just need to run a wire from the plug to F3. I will look this up and add it to this document later on.
Here is a list of things you will need to make your own harness:
First you will need to locate the plugs needed to make this swap work. Try to get both ends of the power plugs and of the instrument cluster from the S13 JDM shell to make your harness. If you do not have these ends, you can either hardwire your harness or you can make your own plugs but you will need to get male and female ends and rewire both sides (stay away from crimps!). I also highly recommend that you double check each pin location and confirm that you are wiring it to the correct pin against the FSM for your car.
Plugs from the S13 SR20DET Harness:
S13 SR Instrument
Plugs off of the S14 KA24DE Harness:
The basic principle of creating a new intermediary harness is to reconnect your S14 accessories (wiper motor, wiper amplifier, CC, and ABS) to the main power plug, F3-S14 KA (which plugs into M63-S14 KA on the interior side). You will also be wiring the S13 SR power plugs to the F3-S14 KA Power Plug and you will wire the instrument cluster plug from the F3-S14 KA Power Plug. Once you have made all of the connections you will be able to plug the F3-S14 KA Power Plug into the M63-S14 KA Power Plug and to the power plugs of the S13 SR, and you will be able to plug in your accessories and your instrument cluster.
First, a few words about soldering. If you don't intend to solder all of your connections, stop reading this right now and figure out the wiring on your own. I do not endorse in any way the use of crimp connectors for your wiring harness. You will only cause yourself trouble down the road and end up having to redo things. Make sure you properly strip all wires and properly solder all connections (do not cold solder your joints or they will fail) and then heat shrink each connection. I then put electrical tape over each heat shrink connection (I am a bit paranoid) and then loomed the entire thing. The last thing you want to happen is a failure of a solder joint or something shorting w/ another wire.
Wire color Key:
Wiper Motor and Wiper Amplifier
F7-S14 KA and F9-S14 KA are both located in the engine bay, against the firewall, on the passenger side. You will only need to make the F7 to F9 wires long enough to connect to each other (make your wires about 1.5'). When you make your connections to F3-S14 KA, make sure you have enough room to go through the firewall and down to the kick panel in the passenger compartment (about 3' should do it). You will need to ground one wire on F7-S14 KA and one wire on F9-S14 KA to the engine. I used a generic grounding wire (make sure the wire is the same gauge as the wire you're using) that I grounded to the intake manifold (where the other two grounding wires are located below the fuel rail).
Wiper Motor-F7 S14 KA to F9 S14 KA and F3 S14 KA (See EL-102 S14 FSM)
Wiper Amplifier-F9 S14 KA to F7 S14 KA and F3 S14 KA (See EL-102 S14 FSM)
Fuel Pump Relay
Connect one wire from F10-S13 SR to the power plug F3- S14 KA (make this wire about 4-5' long depending on where you put your S13 power plugs in relation to F3-S14 KA).
Fuel Pump Relay- F3 S14 KA to F10 S13 SR Harness (See EC-201 S14 FSM)
This is pretty straight forward. You need to power the ecu relay from F3-S14 KA plug and then run wires to the power plugs on the S13 SR harness (make the wires from the relay to the ecu about 1' long as the relay will be left by the ecu and power plug, and make the wires from the relay to the S13 power plugs about 4-5' long depending on where you put your S13 power plugs in relation to F3-S14 KA).
You need to run one wire from the S13 SR power plug to the F3-S14 KA power plug. Make this about 4-5' long depending on where you put your S13 power plugs in relation to F3-S14 KA.
ECU Backup- F3 S14 KA to F8 S13 SR Harness (See EC-85 S14 FSM)
The 1995 KA24DE has two IACV's. I hooked the SR20DET IACV up to the IACV Air Regulator power on the S14. See the S14 FSM for more details. Make this about 4-5' long depending on where you put your S13 power plugs in relation to F3-S14 KA.
IACV- F3 S14 KA to F8 S13 SR Harness (See EC-216, EC-112 S14 FSM)
Ignition Power and Coilpack Power
Make this about 4-5' long depending on where you put your S13 power plugs in relation to F3-S14 KA.
Ignition Power & Coilpack Power- F3 S14 KA to F8 S13 SR Harness (See EC-106 S14 FSM)
Since this is a heated O2 sensor, I wired this the same way the rear heated O2 sensor is wired on the KA24DE (the secondary O2 sensor in the downpipe of the KA). Make this about 4-5' long depending on where you put your S13 power plugs in relation to F3-S14 KA.
O2 Sensor- F3 S14 KA to F10 S13 SR Harness (See EC-164)
Ideally you will have the other end of the S13 SR20DET instrument cluster plug (this is why it pays to get front cuts) so you don't have to hardwire this. If you do not have the plug you will need cut the other end of the harness plug end off of your S13 SR20DET harness and hardwire this (or make your own plug if you are feeling innovative). The wires do not have to be long as they will go from F3-S14 KA to the instrument cluster plug near the ECU plug.
Instrument Cluster- S13 SR Cluster Plug to F3 S14 KA Harness
Once all connections have been made, double check all of your connections and tape and loom everything up. You are now ready to plug this into your harness on your motor and into your chassis. Follow the standard fire up procedures of the engine and make sure that everything works properly. Happy Motoring.
Here are pictures of the harness with all connections made:
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