Supercharged 2GR SW20 Project

[lasersooby]

Picked OEM Ball Joints from Manawatu Toyota today, big ups to the Team there:

ECU Mounting Bracket & Bolts arrived from Frankenstein Motorworks:

Lower Intake Manifold will be packed up and sent to Elate Manufacturing in Australia who will 3D scan it then manufacture a plate intercooler. This will be part of the w2a intercooling system we will have on this car. The lower intake manifold on the supercharged 2GR is different to the NA 2GR hence the reason for sending this to Aussie (the supercharged lower intake manifolds are hard to come by).

[GDII]

Last night I started to strip down the 89-91 JDM 3SGTE MR2 engine harness. Wow this thing is dirty!!!

TLDR; Wires and plugs you need to keep from the 3SGTE harness plus other little bit of information.

You need quite a few plugs and wires for the merge so I'll list them here. I think it covers all of them for this particular swap. It will be slightly different if you are using a different harness. For JDM the GEN3 3SGE has 4 ECU plugs where the rest have 3. The JDM BEAMS 3SGE has 4 plugs but a very different wiring harness so this information won't really apply to it.

Plugs required and the plug name as per the USDM 93 Wiring Diagram. I have used this as it is easy to get your hands on but it is not the same as the JDM harnesses. The actual plug codes for the JDM wiring diagrams is different as shown in (brackets) from document 1989 10 67331.

Inspector Boost at it again. He's really strict on quality control!

Engine Bay Fuse Box
Alternator Charge Wire (Remove this for the 2GR cable)

Plug EB1(EG1)
This is the main power distribution plug. It has power for the likes of Intercooler Fan/Engine Bay fan for 3SGE. Fan Controller. Various VSVs and sensors. Injectors, coil, igniter. Alternator 3 pin plug power and in some applications the Fuel Pump bypass power wire.

Plug EA3(IE1)
This has general sensor signal wires and power switching wires. Such as ABS TC pin for diagnostics, Coolant temp gauge earth, Charge Light, Tachometer signal, Coolant Temp Gauge signal, Oil Pressure switch signal, the wire from the key barrel to the starter relay, in the 89-91 wiring there is the AC idle up valve power and ground wires, these get removed for this swap, Reverse Light switch, AC Clutch power, Alternator Sensing wire and a cruise control wire if fitted.

Plugs in the Boot/Trunk

Plug EA1(EH1)
This has various wires depending on the model and year of car. It's a 12 pin plug for the 89-91 JDM cars but a 15pin socket for the 92-99 cars.
It normally contains wires for the Intercooler Fan system. The 2 engine lid sensor wires and the warning light wire. Speed signal wire and the diagnostics wire for power steering. In the case of this particular harness is the ECU FC pin wire that the allows the ECU to control the Circuit Opening Relay which in turn controls the fuel pump. When the engine stalls, the pump cuts out. It's a safety feature. This plug also has the fuel pump jumper wire to bypass the normal fuel pump power wiring and FC pin for testing purposes only. In the case of the 3SGTE harness there is also the boost gauge signal wire here.

Starter Relay Plug S6 (C)
This remains, no changes needed.

Intercooler Fan Controller Plug C3 (C4)
In Marcs example you use the power wire for the intercooler fan for the AFR sensors on the 2GR as it is fused and switched by ignition already with they right ratings but in this case I want to run a fan for the engine bay as it's supercharged and makes more heat. So at this point this plug remains untouched. Not that it gets modified in Marc example as it's a pin in EB1 that gets tapped into. Just pointing out a difference here.

ECU Plug E8 long and E7 short
This normally gets binned but in Marcs example you can reuse the plugs along with the 3SGTE ECU socket he supplies for joining the Drive By Wire Throttle harness into and merging the body harness plug of the 2GR ECU into plug E6 from the body harness of the MR2 without having to cut E6 off. He shows you near the end of the video.

Cruise Control Speed Sensor Plug
In the 89-91 harness this 3 pin triangle plug exists and is normally not plugged in unless the JDM car had cruise control which is rare. It still exists in the harness no matter what. It has power, ground and signal. In this case we need the wiring from it as Mo is going to an electronic speedo and I'll join in the speedo plug he got from the Camry to plug into his electronic sensor. Normally the older car run cable so the speed sensor has a mechanical spinning cable that runs from the gearbox to the gauge at the front. There the electronic signal is created for the engine ECU and sent back to the ECU at the back of the car. The purple wire already exists in the car from ECU to gauge cluster so we will instead send the signal backwards up the wire to the gauge and also send it directly to the 2GR ECU. All I need to do is earth the ground wire to the engine harness as per the original.

Alternator Charge Cable
Normally for a GEN4 3SGTE swap you need this cable as the Caldina has it in a separate body harness but the 2GR has it's own in the engine harness so you remove this.

Reverse Light Switch
As the 2GR is always Auto Transmission you need this wire to plug into your manual gearbox of choice so the reverse lights on your car work. If you have an auto transmission 5SFE or 3SGE/FE you need to grab the wires and a plug from a manual gearbox and use that.

Coolant Temp Gauge Sensor Plug
You need this wire. Marcs example covers the two methods of using it. In our case we will use the new 3 pin ECU and Gauge sensor in one plug so I can remove this manky plug!

Starter Motor control plug and ring terminal
You need these wires for the MR2 starter motor. The plug is for the solenoid off the starter relay and the ring terminal is a direct 12V feed from the battery via the main cable post on the starter. It then goes to the switched part of the starter relay to the plug shown here.

Oil Pressure Light Switch
You need this wire for your dashboard light but also it has the right signal to make the powersteeing operate correctly with the engine off. Marc explains it in his video and it is in the wiring diagram.

Alternator 3 Pin Plug
On the 89-91 harness the plug is round, on the 92-99 harness it is oval. This, is, oval as it has been spliced to use a newer alternator. I don't need the plug but I do need the wires to join to the 2GR harness. Alternator power, sensing and the charge light.

Intercooler/Engine Bay Fan Plug
I'll be reusing this and attempting to run it through the 2GR harness. Normally you just bin it.

AC Magnetic Clutch Power Plug
You need to keep the wire for this so you can join this to the 2GR harness and control your AC compressor of choice. The 2GR has a pressure valve in it with additional control which makes it harder to use as per the OEM spec. But I've seen that someone welded the valve shut so it only runs the ON/OFF function like the MR2. In our case Mo has sources a 1GR pump from the 4.0litre version of the this engine which has only the ON/OFF clutch function.

OBD1 Diagnostics port
Last but not least (in my opinion) is the OBD1 port from the MR2. Yes, the 2GR is OBD2 and I will wiring in an OBD2 port but.... the MR2 has a few functions that the 2GR powered cars don't have. You can still pull codes from the power steering ECU and ABS if you have it. You can still manually Check Engine Light (CEL) flash the dash light on an OBD2 system but also the MR2 has the fuel pump jumper wire here. Most wires, I'll pull out of this port but I'll keep a few wires here. On the newer system the fuel pump jumper doesn't exist so it's harder to test the pump and fuel system. I like to keep it in as it's useful. I'll relocate this to the boot. The other option would be to run a switch in line with each circuit so you can just run them as they will only be connected to the old TE1(new TC on 2GR) and E1 which is earth and for the fuel pump it's +B (12V) and FP(to the pump).

[GDII]

Now it's time to remove all the insulation tape and plastic coverings from the harness to find all the places to cut wires from. There are many branches and splice crimp connectors hiding inside the harness that need trimmed to remove some but not all wires.

Starting withe fuse box end. The plastic wire clamp here clips into the fuse box. It has to be removed to get the main alternator cable out and some other wires.

Taking off the tape

Remove the cable tie Phill styles.

Put in a safe place for later.

Then start taking of the loom tube. There is very little on this harness.

Starting to expose more wires.

The are the igniter and coil plugs. You don't need the plugs themselves hence the red cable ties but you will end up using the large Black w/Red wires from each later on.

This is how they look under the tape where they join to the main harness run.

A bit more of the harness exposed around the rear firewall boot.

This is where the harness heads off under the intake manifold. It has plugs for injectors and various VSVs for boost (T-VSV) control, T-VIS control and others.

A plastic cover over this part of the harness protects it and holds it in place. Still very dirty in here.
Clips on the cover allow you to open it up then remove the tape holding the plug wires as they break out off the main run inside.

Cover removed, this is what is inside, just more wires.

This is where it branches off after clearing the intake manifold towards the cam belt cover. This is where the OBD1 wires head off, Intercooler fan wires go and O2 and CAT Temp sensor goes along with the AC mag clutch power wire.

Unclip the cover, open it up to remove the wires.

Back to the firewall grommet area.
Remove more thick wire covering.

Removal of the alternator cable. For the 2GR swap it is not needed. For a GEN4 3SGTE, it is!

This is what you are left with. The 2 grey plugs will be cut off eventually but reused. Watch this space.

This fire wall boot keeps showing up. To me, it's rather important. Marc says just cut it as there are so many wires that need to go though it. The just join it with tape again. Not my style, on the GEN4 harness I thread EVERY single wire from the ECU through the grommet 1 by 1. Now the 2GR has MANY more wires to go through being a V6 with VVTi and 4x O2 sensors and 6 cylinders. I'll take a real good look at the 2GR harness once I have stripped it back and make the call. I really don't want to cut it but may not have a choice.

This is the harness part number. This specific swap uses the MR2 harness part number 82121-17300 and the Aurion harness part number 82121-86871 which is actually an NA harness and the old difference isn't a difference at all, just the ACIS plug is not plugged in as the manifold doesn't have it.
Odd fact about the SW20 harness. Part number 82121-17300 is for the SW20 GT from 12-89 until 08/91 however the REV2 car wasn't released until 12/91. So Toyota changed or superseded the harness with 82121-17450 for 4-5 months. I wonder what they changed? The next harness has part number 82121-17301 for the REV2 car which I know is very different.

This Green w/Red wire is the FC pin on the ECU. It controls the C/OPN Relay or Circuit Opening Relay which essentially controls power to the fuel pump. This realy gets switched when the key is turned to Start and when the ECU is happy the engine is running it powers up the FC pin and keeps the C/OPN relay closed. When the engine stalls such as in a crash the ECU shuts off the pump. Safety feature. Now in Marcs example the FC pin exists in Pin 14 of Plug E6 which is the 22 pin ECU plug that is part of the body harness. This makes it easy to redo and splice the new ECU FC pin to this wire. However in the JDM REV1 harness the FC wire is of course somewhere else. It exists in Pin 17 of Plug E8 then goes to Pin 2 of Plug EA1 which connects the engine harness to the body harness. I will need to rearrange this to make it work, I'm sure it's not hard but I have not spent any time to think about how to come up with a solution. I recall on Olafs car I just ran a new bullet connector plug outside of all the OEM plugs to make it work for his 3SGTE swap, but I'm not going to do it that way for this car.

And this is how the harness looks stripped of it's tape and wire loom covering.

[GDII]

Now to actually start removing plugs and wires from the harness. I've already removed the alternator charge cable but that's just taped in place so easy to remove unlike the rest which needs depinned or cut out.

Starting at plug EA3 with the 89-91 AC Idle Up VSV wires. These are not needed as the 2GR now has an electronic throttle so the ECU can just add air as needed with the throttle plate instead of an external bypass valve. This plug and wires can just be depinned and put aside.
The wiring diagrams explain how to unlock and depin these type of plugs.

This is the harness tape in the bin. Plenty of it. The tape can go really hard if exposed to heat and oil and it's also lost most of it's sticky yet it's so so dirty!

The coil ground with had some damage to the outer casing. Not great but luckily we don't need to use this. The other wire however, useful to have for powering coils and injectors as mentioned previously.

This is an overview of the harness before stripping it out.

This photo probably puts fear into a lot of people. The stuff nightmares are made of. It just happens to the be the location where most of the wires run along side each other so nothing to be scared of.

Showing the age of the wires. Yazaki 1990. Yazaki manufacture Japanese car wiring harnesses and started in 1939.

Alternator wire in the fuse box. This has 2 nuts with studs holding it in, the 2GR has a single stud so you only use one.

And it starts. Ready to start cutting!

These older harnesses use a wide bit of tape to cover and seal the splice crimps from corrosion. It does work as the copper and brass is still fresh 30 years on.

This splice is for the power wire from ST2 in the key barrel(START) to 4 items in the JDM GEN2 3SGTE harness.
1. Starter Relay coil. You power this coil and the switched side closes activating the starter motor. Obviously you only turn the key to the START position until the engine is running so the other 3 items only get power in this situation.
2. Cold Start Injector
3. Cold Start Injector Time Switch.
4. STA pin on the engine ECU. This appears to receive power from the key for the 3SGTE. In the 2GR swap you don't need this pin hooked up to the 2GR ECU as it actually provides power to the Starter Relay coil rather than the key so backwards to the MR2. As we are using the MR2 starter relay system this pin is not needed to be joint in to the ECU. You'd probably damage something if you did.
The 2GR ECU has a pin called MREL which is Main Relay (read EFI Relay) so the ECU controls the EFI relay where in the MR2 this is controlled by the key. So we actually bypass this system as the ECU doesn't seem to care.

Going in for the first cut!

Executed!

This is the 3SGTE harness next to the 2GR harness. I'll cover the 2GR harness in a bit more detail later on.

This splice join is from the Coil, Igniter and Noise Filter. All three are to be reused for 2 coil banks grouped as 1,3 and 5 and 2,4 and 6 and the fuel injectors. This is contrary to Marc's diagram as the USDM 93+ shows Injector power coming from Pin 4 on EB1 and coil power from Pin 10. So it is different for the car and you need to check. I know the GEN3 3SGE has the Coil in Pin 2, the Injectors on Pin 4 and the Igniter in Pin 5. Always check the actual car and harness you are working with.

Marked to join to the following wires on the 2GR harness. Coils are CA3 Pin 2 and Pin 7 and Injectors are CA1 Pin 2.

All the stuff you don't need in a pile.

Progress shots at this point in the stripping process.

Ever wondered what was in the back of the OBD1 port. Nothing special, just wires as per the typical plugs.

All these wires that remain for EB1 (small) and EA3 (large). Note the long black wire, this is for the Tachometer from the ECU. I'll be using the resistor swap method to convert the 4 cylinder signal to the 6 cylinder signal. The rest of the wires are power and signals to parts on the car body, mostly dashboard.

This is what is left on one branch of the harness. Starter motor, Coolant Temp Gauge Sensor, Oil Pressure Switch Light and Gearbox Reverse Switch.

On the other branch is the Intercooler Fan plug, Alternator 3 Pin plug and the AC Mag Clutch Power plug.

Here is OBD1 and the main earths for the ECU and sensors. I'll be cutting out most of the earths, I just haven't go to it yet but some will still remain.

An overall of what you end up with after cutting it all out.

To protect the Injector and Coils OEM splice I will put heat shrink over it. To do so I have to depin the plug to run it over the wires.
Unlocking the retainers

Unclipping the retainer to pull out the pin.

EB1 Pin 4 removed.

EB1 Pin 4 and wires marked out.

I'm using Raychem ES2000 No.1 and No.2 which is a dual wall adhesive lined heat shrink so it seals the area inside the shrink once it has been recovered in size plus gives a stiff area to protect it.
I have to go with No.2 size to get over the pin as it's very big.

Shrink it with fire!

You can see the glue coming out each end.

That's it for now. Something to note, I'll be reusing the 2 grey 3SGTE ECU plugs so I cut the wires instead of depinning them for future use. Normally I depin to retain the wires from the ECU to plug where I can incase someone needs a whole length of wire to repair or extend their harness. Of which has happened before.

[GDII]

From the last step in stripping the GEN2 3SGTE harness I had cut a lot of the wires for unused plugs to leave some length on the two spare ECU plugs E7 and E8. This is so I can use them on the jumper junction block that you can buy which is a GEN2 3SGTE ECU socket. Everything from E7 and E8 gets cut or removed.

This is one side of E7.

This is E7 that I will hook up to the 6 Drive By Wire Throttle Pedal Position Sensor plug and wires supplied by Frankenstein Motorworks. I am yet to confirm of the length for these wires is long enough for a RHD car. I feel they are not based on a quick test fit. I need to be sure so I can lengthen if required.

I need to remove a few more unused wires that are connected to the OBD1 port through EA3. This one being the yellow TS for the ABS ECU of which does not exist in this car.

Removing the CCO wire as it is from the Cruise Control ECU of which this car does not have. Plug EA1 in this case.

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Removing ECU plug E8 for use in the junction block. More to come on that later. As you can see there are 3 earth wires. These are the main earth wires from the 3SGTE ECU. E01, E02 and E1.

These earth wires go to the main ECU earth point on the intake manifold. A 10mm bolt holds this eye terminal on. You can split it if needed. I have done so as t takes the earths from other sensors out. I'll be splicing the wires onto the 2GR harness earth point of which there are some spares when you remove the transmission ECU plugs out.

I am attempting to not cut the firewall boot so that means pulling each wire through it one by one. 76 from the 2GR harness and a few from the MR2 harness. I'm relocating the OBD1 port to the boot space as it has the TC pin for pulling codes from the power steering ECU, E1 (earth) +B (12V Power) FP (Fuel pump) and TE1 (CEL flasher).
Why? Because the new wiring harness does not have a way to jump the fuel pump for testing like the older systems do. So you jump FP and +B to make that work. TC and E1 for getting powersteering ECU codes and TE1 and E1 for getting OBD2 CEL flashing codes. Yes, you can CEL flash OBD2 engine codes without a scanner tool. If you have old school MR2 knowledge it's still there for use. You can also CEL flash using a wire to jumper the OBD2 port too if you wanted to. I just hook up the TC pin on the OBD2 (DLC3) to the TE1 wire for the OBD1 port. Easy.

I use a wire to pull each wire through.

Now I need to move a wire for the FC pin (Green w/Red) which is Fuel Cut from the ECU. It lives in plug EA1 and E8 on the 89-91 wiring which does not make it easy to do the swap. The example Marc gives uses the 93+ USDM which is similar to the 92-93 JDM wiring where FC is already in plug E6 in the body harness. Simple, just get that from the new 2GR ECU into the junction block you'll be making and go! Here on the older cars, not so much. I mentioned before that I hadn't looked at exactly how to make this work. Now I have after throwing together 2 options. First option did not work, it's ugly and involves a stupid single pin plug to jump from one place to another. Second option is to modify the body harness on the car and move the FC wire from EA1 to E6(need a new terminal) and then use the junction block as per what Marc shows to get power to the right place. I'm going with option 2.

Now E8 can be removed from the 3SGTE harness.

This is what you are now left with. This is sufficient to now merge with the 2GR harness. Wires will get cut short but not all.

[lasersooby]

I want to thank Grant Rolfe - Engineering Supervisor at my work for helping out massively on the re-assembly of these parts. Amazing how quickly things happen when you have the right tools to do the job, especially hydraulic press etc.

Assembling of the lower front arms with Prothane Bushes that I bought through TwosRUs:

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This is what the Megan Racing Adjustable tension rods looked liked prior to making some changes:

The studs in the MR tension rods were 10mm x 1.5pitch x 30mm long:

The OEM Toyota Tension rod studs are 12mm x 1.25pitch x 48mm long:

I could not find the correct stud length, ordered some longer studs then modified them to fit the tension rods:

After mods and painted black to blend in the rest of the suspension parts:

Installed the lower suspension arm:

Installed the tension rod:

Reassembled the front hubs with new bearings etc. The only old items in the hubs are the actual hub and the ABS rings with the ABS sensors. By the way DO NOT FORGET TO INSTALL THE DUST COVER FIRST, we found out the hard way

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[lasersooby]

Purchased the full Suspension Geometry Kit from Wilhelm Racing to sort out the additional adjustments on the suspension including the roll center adjustments.

Front Kit:

Kit installed on the hub:

New ball joints installed:

[tomnomnom]

Do you know if that Wilhelm kit can be road certified? Have you had it tested?

[lasersooby]

Hi mate, been working closely with my certifier on this and have asked him again before installing this. If he changes his mind once it comes to certification time, then I'll have to whip out all the emails etc thats been going between him and I.

Also, no I haven't tested it nor had it tested.

[ClanFever]

Will be interesting to see how it gets on - https://www.lvvta.org.nz/documents/stan ... ystems.pdf - this does say you are allowed to change the components so I don't see why there would be any issues, it looks like the kit is very high quality and actually helps to remove some issues with the stock MR2 suspension

[GDII]

Will be interesting to see how it gets on - https://www.lvvta.org.nz/documents/stan ... ystems.pdf - this does say you are allowed to change the components so I don't see why there would be any issues, it looks like the kit is very high quality and actually helps to remove some issues with the stock MR2 suspension

Buying Alex's coilovers might be another issue but they aren't used here. They are custom welded by him.
In saying that, his weld quality is probably better than my OEM swaybar link bracket from Bilstien that failed because the weld was faulty.

[lasersooby]

Will be interesting to see how it gets on - https://www.lvvta.org.nz/documents/stan ... ystems.pdf - this does say you are allowed to change the components so I don't see why there would be any issues, it looks like the kit is very high quality and actually helps to remove some issues with the stock MR2 suspension

Thanks Olaf, it's possible that he is interpreting things similarly which is good for us

[lasersooby]

Finished installing the new rubber of the T-Top, looks really good and solid. Once it is up and running, will have to check it out for leaks

[lasersooby]

Installed the HSD coilovers in the front. Encountered a few minor issues and these were resolved as we went through the install process. Thanks to Grant Rolfe for the help in doing the swaybar link bracket and also to Phil for identifying a mistake I had made when I installed the lower front arms. It was missing the washers in the front of the inner bushes.

Shock absorber bolts cleaned up (combination of meth & turps) and ready for install.

Dis-assembly of coilovers so that I could install Alex Wilhelm Raceworks top camber plates:

Comparison between the top hats & nuts (HSD vs AWR):

Re-assembly of the coilovers with the new AWR camber plate:

Installed in car, please note that Picture 28 shows the shocks installed incorrectly, it is 180 degrees out from the original position:

Hub mounted on coilover:

We had to modify the sway link mount on the coilover. It was too close to the inner guard and there was no way we could have got the swaybar link in there. The difference between the OEM setup and the coilover was 10mm. Grant unstitched the welding, removed 10mm off the lug then TIG welded in place then re-painted so that it looks just like original HSD item. He made sure to get the angles right so that the link would mount the way it should

Test fitted the new rotors (Rotor is off a Lexus LS 400, diameter of rotor is 323mm), hmm, have a bit of modification work to do on the dust shield

Difference between the OEM rotor vs the new setup:

Swaybar link bolts need to be modified, cut short by 6mm so that it clears the inner guard. This will get done this week:

[GDII]

Starting work on the 2GR harness.

First off you start with the main engine harness ECU plug. Most of the wires in here stay. You choose to remove any unneeded wires.

These are the gearbox and starter motor plugs. And the MAF plug.
Plug C1 is the select lever wiring. It tells the ECUs what gear you have selected. For this harness you remove all the wires but Pin 1 and 7. 1 is power and 7 is drive. In Marcs example it's 2 and 7 as that is how the RAV4 is wired.
Pin 1 is red and pin 7 is green. Cut and join these to put the ECU into Drive tune mode permanently. I'll cover this later on.

These are the 3 fuse box plugs you need to grab wires from to join to the MR2 harness.
I'll cover in a bit more detail in the next post. It won't show everything but the idea behind what is trying to be achieved.

This is where everything in question lives vs each other. The MAF and coolant temp sensor plugs are here too.

These are earth splices epoxy sealed. I'm yet to actually determine what earth wires these join but they probably need to stay here near the ECU plug.
EDIT: These are for the shielded cable earthing connections. Makes sense why they are at this end of the harness.

Removing a clamp that is used to clip the harness to a clip. This one probably won't go back on.

Starting to take off the tape. This stuff is sticky!! Well sealed!

Removing the loom tube.

The Aurion has the battery earth cable in part of the harness. Time to remove that as it is not needed.

This is the alternator cable. It's a single eye vs the double eye in the MR2 harness. You need to remove it from the plastic clamp from the Aurion fuse box to use it in the MR2.

This is what you are left with on this branch of the harness before you remove the unused wires. I've marked each one I need to keep.

This plug is interesting. C34 is for the ACM vacuum switching valve. It is Active Control Mount for the engine mount stiffness. It varies vs RPM to smooth out the vibrations on the engine. Idle is an RPM where it helps make the engine feel smoother. This gets the chop! Unless someone wants to figure out a way to use the mount in the MR2.