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

icemhan_21

so i could use the s14 ka ac compressor to s14 sr with no problems?

TTrx7Pete

Correct. You will just need to have the correct mounting bracket. Someone on the forum sells them. You use your USDM connector to the a/c compressor.

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1993 AW Mazda RX-7
1997 Nissan Silvia

s15specR

dude this is GRRRRREAT!

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TTrx7Pete

Yeah hopefully it will help out a few people trying to do this swap.

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1993 AW Mazda RX-7
1997 Nissan Silvia

MyLevinGTZ

ok, i just went through the harness again, and this statement is wrong according to your drawings. the pin out you listed is if you are looking at the face of the plug, not the wire side.

messed me up when i started, but after that it was cool. am missing a couple of pins but i cross referenced with another post and they weren't needed anyways (boost sensor, and consult)

just wanted to note that so you could change it. keep people from making the same mistake as me.

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HPballer76

//quote// 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. \\quote\\

so it dosent matter which maf [69F00 or 69F01] as long as the plug on your harness matches the plug on the maf? please help been searcing for a while

TTrx7Pete

Correct. I've hooked up both #'d MAFs and they both worked the same. As long as it is oval and your plug is oval, it works. Same goes for the Black WC and Red WC ECUS.. there isn't a difference.

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1993 AW Mazda RX-7
1997 Nissan Silvia

icemhan_21

do we really need to buy custom heater hoses? i thought we could just cut the stock ka heater hose and itll fit right in to the sr?

TTrx7Pete

Actually you can... but you can risk some pinch on the hose. You can actually use the hose parts that come out of the heater core that include the plastic joiner piece. However, I recommend using S-shaped hoses to connect to them from the engine. The KA ones could be cut, but they tended to bind up a bit and I'm not satisfied with having a tiny bind in a coolant line. It's really a question of doing things half-assed or not.

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1993 AW Mazda RX-7
1997 Nissan Silvia

devonkyle77

can you explain this a little more? why can it result in damage if run to the throttle body?

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WTB-NARDI wheel & NRG 2.8 QR

95KA-Turbo

Nice write up. I did one of these swaps with the help of a few friends who had done it before. Finding write ups and wiring is a total bitch!

We used this in conjunction with having both service manuals open next to each other and doing each wire individually that needed to be swapped.




Also for the wipers (At least for a 97 240) all I did is cut the KA plug off the KA harness and the wire colors matched right up to a Zenki SR harness. My wipers have all of their original functions, probably the easiest part of the whole swap actually...even though I didn't think this swap as very difficult at all, time consuming yes, but really not that bad. So I only changed the one plug, not sure if that matters.

I also cut my heater core hoses off the KA and connected them to the SR with out any crimps or bends, so it is possible but buying new hoses is definitely a great idea.

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Instagram - SJKnoop

TTrx7Pete

The only other thing I forgot to mention was that on the engine harness there will be 3 plugs you will not use. These plugs are located right where you will plug in the ignitor. One is a spade connector that looks like a T, and 2 are small plugs. On the JDM S14, the wiring harness comes over on the driver's side and these plugs plugged into things on that side, so there isn't anywhere for them to go on your car, since now your wiring harness is on the passenger side. Just cut, strip, or tape back these plugs... not needed.

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1993 AW Mazda RX-7
1997 Nissan Silvia

TTrx7Pete

Sure. Your wastegate actuator is activated as the mechanical diaphram inside receives boost. The closer the vacuum/boost line is the less distance air is traveling. While this seems like a novel idea because it is hard to grasp that distance REALLY does matter with air travel, the wastegate receives a strong "clean" signal the closer the line is to the turbo outlet. On high horsepower applications, the wastegate signal usually is tapped into the compressor outlet housing itself. A split-second of high-boost application can wreck your engine if the wastegate is not able to react in time.

Don't believe me? Call any speed shop or race shop and they'll tell you what I'm telling you. Running it to your throttle body is dangerous if you start to boost anything worth being happy about.

Some people do run it to the throttle body - but this is incorrect and dangerous. The signal is not going to give the wastegate the correct reading in time. You can risk this yourself, but having worked on high-horsepower engines for a living, we always ALWAYS make sure the signal is as close to the turbo's outlet as possible.

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1993 AW Mazda RX-7
1997 Nissan Silvia

icemhan_21

i cant find any of those s shape hose for s14..i found a lot of them for s13 from heavythrottle but they have to sell it like a package with the u shaped hose..

TTrx7Pete

Just go to an Autozone, Advanced Discount Auto, or NAPA and ask to see all of their heater hoses.

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1993 AW Mazda RX-7
1997 Nissan Silvia

devonkyle77

so how do you go about putting a nipple on the hotpipe? where do you buy said nipple?

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WTB-NARDI wheel & NRG 2.8 QR

TTrx7Pete

You can go to home depot or lowes and buy a threaded barbed nipple from the hardware department. Then find a bung to weld onto your hot pipe from your local friendly speed shop or welder.

Have them cut a hole in your hot pipe, weld the bung, thread the nipple in. Done.

Or

Have a custom hotpipe made at your local welder or speed shop who can weld an aluminum or steel (depending on your pipe material) nipple on.

Anything else?

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1993 AW Mazda RX-7
1997 Nissan Silvia

devonkyle77

nope, fantastic info, thanks for the help kind sir!

i need to buy a hotpipe anyway, just wish they had the nipple already installed to make my life easier. cant find em like that though, lol

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WTB-NARDI wheel & NRG 2.8 QR

nzmoman

I ran my wastegate to the cold pipe nipple that came with my fmic. I was told that this is an okay place to run it as it is before the Throttle. Even though its not really close, the way I understand pressure is that it doesn't flow through the piping it exists throughout the piping at the same rate.

I guess the difference as I understand it is putting water in a tube vs putting air in your tire. Water in a tube flows and there can be more of it in one place than another.

Air pressure in your tire is universal throughout the inside of the tire. So as you put air in the tire there is not one place inside the tire that has a lesser or greater pressure in the tire it is changing all at the same time.

So I wonder, what would be some of your opinions on a location other than the throttle? I am by no means an expert, but the physics of gases makes me think that as long as its on piping between the turbo and throttle then it will give almost the exact same response... (this is also taking into account pressure drop with large FMIC kits as the actual pressure going into the motor is on the cold pipe not the hot pipe) I am only running 7-10 psi on an S15 BB T28...

any input?

TTrx7Pete

You are right about pressure.. but the problem is that there is a pressure drop at the FMIC as well as close to the throttle body when the throttle plate is opened. Like I stated before it's hard to grasp this because we think of the pipes being pressurized in their entirety to say 10psi. That is true, but the problem really lies with the distance this pressurized air is "traveling." Pressure will always be greater in the instance it is created at it's source. This is why you want that nipple right at the compressor housing or hotpipe. It is the "closest" you can get to a "clean" pressure signal. I'm not a physics major or anything, just a humble lawyer, so I can't really explain it in depth, but I'd be happy to ask my father, who is an engineer exactly how to explain it better later.

As for the nippled s14 hotpipes, they don't exist, I did a lot of searching. GReddy supposedly used to make one, but most of the time now you will be making one or buying a cheap chinese one from Heavy Throttle, which does not have a nipple on it. I bought mine from Heavy Throttle and welded the nipple on it.

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1993 AW Mazda RX-7
1997 Nissan Silvia

slow_talon

This thread cleared some of my questions...Good Info here...

Pstl_pete

Great info, I was looking for something like this. Ill be swapping an S14SR into my bros S14 and I was going to send the harness out but I may attempt it myself now.

For the lower harness, can you post a link to a thread off here that is correct and explains the wiring? I think it will be worthwhile to have in this thread.

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S14 - New SR Project
http://www.speed.academy

TTrx7Pete

The lower harness isn't any different. You don't have to modify it, it is only different if you are converting automatic to manual transmission.

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1993 AW Mazda RX-7
1997 Nissan Silvia

Vandy5

Sorry to bring up an old thread just lost on a bit of wiring


My s14 was an automatic and my new sr is a Manuel so what does that mean I'll have to do on the few lower harnesses

eastslider

just means that you would have to wire the reverse lights and speed sensor in urself since its not there and connect the neutral posi switch to complete dat circuit. the KA lower harness is used on the SR so you dont need to modify anything.. thank goodness..

eastslider

well i tried seeing if the fuel pump would turn on and it doesnt.. just my luck... all i get is a click coming from the exhuast side?/ please help... and out of curiosity i tried turning the starter andi get another click coming from the exhaust side... please help....

MyLevinGTZ

can you verify the white diamond? i'm going through a harness now and there are quite a few discrepencies. are pins 10 and 23 black on your harness? because the are blue/yellow stripe and black with yellow stripe on mine.

that's using the "look at the wire" side of the plug.

thing is, if i look at the face of the plug, and use that same numbering scheme, 10 and 23 are black and a couple of wires aren't missing any more.

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Nolmack

Wow what a great write up, thats too bad this wasn't out while i did my swap, but I noticed that you arent supposed to run the vacuum line from the throttle body to the actuator. Wondering why? and also, if anyone has a vacuum line diagram.

icemhan_21

vacuum diagram:



and wc zenki s14 pinouts