TTrx7Pete

DISCLAIMER: DO THIS AT YOUR OWN RISK!

This thread is a basic how-to for installing an SR20DET Blacktop/Notchtop out of a JDM S14 into an USDM S14 Chassis.

First: This original post will not contain pictures, I'm in the process of taking some pictures. This post will not contain step-by-step pictures either, rather it will contain relevant information for doing this swap.

Why I'm doing this: The forums basically do not have any straight answers regarding this swap because it is deemed "difficult" compared to stuffing an S13 SR20DET into an S14.

I am also NOT claiming credit for the wiring diagram that is posted in this thread. This was the work of someone off of FreshAlloy, but finding and obtaining this wiring is almost impossible nowadays.

STEPS:

1. Remove your KA. This is relatively straight forward. If you are doing a motor swap, you should be able to remove your old engine.

Tips: Keep the engine and transmission whole when removing. Also remove your wiring harness from the ECU and pull through. Also disconnect your upper and lower harness where it mates to the chassis. This will allow you to pull the entire engine and harness as one complete piece.

You will need to keep your lower and upper harness from the KA. If you have air conditioning, you can remove the A/C Compressor and keep the lines intact. This will allow an easier install of the A/C once you have installed your SR20DET.

2. Clean and straighten out your engine bay. KA's as like most Nissan engines are known for horrible oil leaks. Clean it up. I was lucky enough to be doing this at a local FORD dealership and we had a steam pressure washer... it makes short work. I recommend a pressure washer, go rent one, don't bother scrubbing for hours. This will also work on your new SR20DET. Hose it off!

3. I decided to install my SR20DET without the transmission because of my availability of a transmission jack and lift. You can install it together or separate, your choice.

Tips: Make sure to inspect your motor mounts. Your KA motor mounts will work on your SR20DET if they are in better shape. I also recommend replacing your ECU Coolant Thermostat (thanks ZUL8TER) while the engine is out. Replace your belts as well. Tensioning will be much easier with the engine outside of the car. Change your oil filter as well, this is a real bitch inside the car.

Check your timing! Search on this, covered billions of times and the FSM!

Basically look over your new baby and make sure everything looks tight and good to go, inspect any and all gaskets you can inspect at this point.

I also removed my engine fan because I was going with electric FAL fans, your choice... But if you do keep your fan, make sure you have the JDM shroud, or it is pointless...

4. Heater hoses are normally thought to be a real pain. You can buy the Heavy Throttle ones or go to Autozone and buy hoses. Generally you will just need two (2) S-shaped hoses. You can cut these to fit. The heater hoses will basically line up with these S-shaped hoses and give you no problems whatsoever.

5. Install any upgrades such as your radiator, fans, intercooler, hot pipe, BOV etc.

6. Wiring: The wiring involved in this swap is pretty straight forward. It involves only repinning the F4 to M63 plug. You will need to follow the attached pdf document to correctly wire the engine. You will notice a black diamond and a white diamond on the plug depiction. The black diamond signifies that you are looking at the plug itself while the white diamond is telling you that you are looking it from the back (i.e. the wires themselves) Remember you are REPINNING, which means you should be looking at the WIRES not the plug...This wiring WORKS. It isn't a secret. Do NOT pay someone to do this if you have any skill with wiring! Also, do not use RADIO SHACK wiring butt splices or soldering or HOME DEPOT CRAP. Go out and get you some aeromotive grade connectors and crimp. I recommend AMP. Do a search and find yourself a deal...

However, the boost sensor DOES NOT need to be hooked up or wired, it is junk now... (per WIRING SPECIALTIES) They told me that they do not wire this up.

Additionally, the wipers: The wiper AMP is located on the passenger side behind the strut tower. It is a brown box. You should have seen this when having to remove your KA. You will need to cut the SR's wiper amp connector, which looks like a big white connector. Use the connector from your KA harness, matching the colors up. You will also need to do this for your Wiper Motor.

Once you have your wiring completed, you can sling the harness into place. You will then of course notice something... your MAF wire and O2 wires are not long enough... not a problem. Grab your trust KA harness and find the MAF plug/wires and cut all that you can out of it. Do the same for your O2 plug. YOU MUST USE THESE WIRES! They contain a shielded wire which must be correctly reattached. Make sure you match up your wires correctly and make sure you reattach the shielded part of the wire to the SR's shield. This shield runs a ground which disrupts "noise" from the other wires, thus giving the ECU a clean MAF and O2 Signal. You can also reuse the heat wrap that goes around the O2 sensor's wiring since it will be along the back of the engine.

Another thing you might notice: One of the SR20's plugs will not mate to your USDM chassis harness. Grab that trusty KA harness and find the corresponding plug. You will notice that the SR20 harness has more wires than your KA did for that plug. Again, match them up properly and strip,remove, or tape and pull back the ones not in use.

Another thing you will notice is that the SR20DET has two big BLUE plugs that are down by the ECU. You'll notice that your KA only had ONE Big BLUE plug. That big blue plug had a relay sitting on it... grab it. This will be for your ECCS relay. You will need to get ANOTHER ECCS relay from the junkyard or your local friendly Nissan dealership. The CAR WILL NOT START without BOTH relays hooked up. DO NOT jumper this!!! You risk damage to your harness! The second relay that you currently do not have is for your IGNITION! Without the relay you will not get any spark. Install it.

Transmission wiring: You can find this anywhere on Zilvia if you are doing an automatic to manual swap. Manual to Manual, it is your choice on which lower harness to use, KA or SR.

Myths:

Black and Red WC ECU = There is not a single difference between these ECUs. WC is used for the Zenki and Chuki engine harness. The Kouki uses an NA harness. There is a HUGE difference between these harnesses. The WC harness uses a much bigger ECU plug while the NA is must slimmer and not as long.

MAFs: Oval vs. Rectangular. You WILL need a retangular MAF if you have a RECTANGULAR plug on your WC harness. However, certain WC harnesses use an OVAL plug like the Kouki harness. Most people think that this means that the harness if from the Chuki series. This is true. However, there isn't a single difference between the OVAL MAF of the Kouki and the Chuki. Lesson: Make sure your MAF plugs are identical to each other and you will have no problems.

Wastegate Actuator: You MUST run your wastegate actuator's signal vacuum line CLOSEST to the turbo outlet pipe. Recommend tapping and having a nipple put on your hot pipe as close to the outlet as possible. DO NOT run your wastegate actuator line to the throttle body... this can result in serious damage to your engine!

OK... Now you have the engine in the car, you are wired up, you have a full battery... Time to double check everything. Make sure you have installed your wiring, both relays. Make sure you've tightened down the 10mm bolt to the ECU and the lock for the F4/M63 Plug.

Turn the key to the ON position, not START. Verify that your guages are not going all wacky. Verify that you have your BRAKE, ABS (if equipped), and CHECK ENGINE LIGHT. Your S14 ECU Does NOT, have an LED light on it to tell you when it has power. Instead, your ECU tells you that you have power through the CHECK ENGINE LIGHT at the ON position. If you see this, you have power to your ECU, congratulations. Now take the key out...

Disconnect your ECU. Crank your engine over a few times to prime your oil pump, if you remembered to put oil in your engine...

Reconnect your ECU. Verify the same as above, attempt to start!

It should crank without any problems, next will be your hunt for vacuum leaks... enjoy.

Questions? Comments? Feel free to post. I will be trying to provide some pictures later on.

Attached Files

Wiring.pdf (55.7 KB, 2971 views)

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1993 AW Mazda RX-7
1997 Nissan Silvia