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Spectacular. Bringing back so many good memories. Engine is such a pain in the *** to get in. So worth it. Outstanding job!
I could write a book on the many great things I'd like to say about your project. For now, great job sticking with it.
Thank you very much, sir!! I've seen your extensive build thread before and I also could go on about your attention to detail and stealth approach! I saw you updated it just recently intending to take your SC back to daily status soon. Love your car! Are you still running the same STU GT28 USDM turbos?
Apologies, everyone, for the long delay in updates. The simple reason for this has been the lack of time to slow down enough to tend to this thread until now. It's been one mini project after another under the car or with my solder gun and many of those sleepless nights in rain, 75% humidity and dousing myself in mosquito spray (strong but DEET-free type with as much as I used) and Bactine all the way through. The push has been exhausting for me but when you want... and need... a project done sooner rather than later, you keep going
I swear, I'd be very happy if we could replace mosquitoes in the ecosystem with something else that doesn't go after blood. I'm going to start making yeast-based CO2 traps for the little buggers.
Anyway, let me catch up here. I will not be going over EVERY task associated with reinstalling a JZ engine into an SC since some of the steps are just very common and there won't be pictures of every single thing that I did (mostly because I was either trying to be done for the night or constantly respraying for those little blood-sucking devils) but I am covering all of the aspects that stand out when compared to your average non-stock JDM 2JZGTE swap.
Back to the engine mounting installation issues I was having
(Nov 2019 Revision Note: After doing some more research on these JZ engine brackets long after this was swap was completed I am of the mind that these are probably NOT 1997-98 Supra engine brackets but rather early 1JZ engine brackets of some kind... I would say from an '89-'92 Supra 1JZ but that cannot be the case since the date stamping on the back of them say "94". Still a mystery as of this revision.
2nd Revision Note: After even more research into this I am strongly of the opinion that these were actually early GS300/Aristo 2JZ engine brackets. They have "94/9" stamped on them and this would suggest a 1994 or 1995 model year GS or Aristo 2JZ engine they came from. Their longer width makes more sense in the GS/Aristo engine bay and only the later 1997+ GS300 and 1997+ Aristo came with the "round" looking 2JZ engine brackets that the internet is far more familiar with. Anyone encountering this same issue with their swap take note.)
This turned out to not be so obvious but a very simple reason: I was using the wrong engine mount brackets! After much exhaustive research and help from Gerrb it was determined that what I had on the block initially were probably the engine mount brackets from a Supra MKIV that are intended for the longer type fluid-filled engine mounts.
Some comparisons of the Supra MKIV (not sure which years they cover) brackets and the early SC300 engine mount brackets:
The easiest and most accessible solution for me was to remove them and swap on my original 1993 2JZ-GE block's engine mount brackets. I cleaned them both up first and then removed the GTE oil cooler to do the intake side (I double checked the torque on all bolts upon reinstallation of the cooler).
The turbo side was a little more challenging. The lower exhaust collector with the ceramic valve allowing turbo #2 to be blocked from or allowed exhaust transition pressure had to be removed first. I did this with the engine crane lifting the engine slightly off the tire cushion.
With JDM or USDM stock twin turbochargers there is a Y-shaped oil drain pipe that runs underneath the turbo/exhaust side engine mount bracket. And the GE exhaust side bracket from my old engine was hitting this drain pipe hose which prevented seating it correctly.
This is what had Gerrb and I confused for many hours until I realized the blockage was caused by a non-structural part of the casting which identified the manufacture date of that bracket. I took it to a grinder with a stone wheel and gradually took that protrusion down to a completely flat surface in line with the rest of the underside of the bracket. NOW it fit on the block over that OEM GTE twin oil drain pipe with no issues!
Also, on early SC300's with original engine mounts there are two thick metal plates and on one side there is a thin steel insulator shield. These are NOT used with the MKIV engine mounts. They were intended to protect and insulate the softer OEM Lexus SC engine mounts. The MKIV engine mounts are steel encased and do not need them. They also get in the way and prevent correct engine mounting in the chassis.
So the parts in this picture below are no longer needed (unless you plan to use stock SC300 engine mounts).
Finally, I was WRONG about the engine crane hoist I had been using up to this point
In what is definitely up there with one of my biggest snafus, I was in fact using a 1-TON engine hoist rather than a 2-ton. I'm not sure when I became mistaken and assumed I had a 2-ton crane but many months back I probably figured that a 1-ton crane was affordable enough and good enough for the engine weight when I had originally bought it.
In the real world the front bumper and front crash support did have to be removed and I DID need a 2-ton hydraulic crane for the extra length at the maximum extension length (which allowed for a 1/2 ton rating at max length rather than a 1/4 ton rating at max length with the 1-ton model crane). On short notice I was able to pick up a fully assembled good condition floor demonstrator 2-ton model at a Northern Tool store and get it back to the garage with the help of my uncle and his truck. They did work with me on the price just a bit but when you need the right tool for the job, it'll cost you
...
After all of that, on the next try it was still difficult to get the engine and transmission aligned correctly but now the 2JZGTE and R154 went IN!
It was a huge relief and sense of amazement to actually see it in there. Directly after that I went about reinstalling the old improvised/welded/extended 1982-85 Celica W58 crossmember I've been using with the MKIII R154 since 2013. The mounting holes were tight and I needed to bore them out just a bit but the driveline was straight in the car.
Later I am going to look into the one aftermarket transmission crossmember that is made for this style of R154 and the SC/MKIV chassis.
Last edited by KahnBB6; 11-21-19 at 01:46 AM.
Reason: Added notes regarding the mystery 2JZ engine brackets that would not fit the SC's crossmember.
Notes among all the numerous things reinstalled, bolted up and custom wired after getting the engine in
I noticed when taking out my R154 slave cylinder that the little internal piston boot had ripped. I was able to get it back on and reinstalled correctly (and I did not forget the electrical ground wire that goes on when you install the slave cylinder) but I have to wonder if this won't cause an issue down the road. A cheap transmission part to replace and the fluid was still in there so I just bolted it back in as is. I turned the little rip away from the internal clutch assembly before inserting it.
Converting the 2JZGTE 6-speed harness manual transmission backup sensor connector
I'm trying to remember exactly what I did here but I THINK what I determined was that it was easier to change out the engine harness connector for the transmission backup light than it was to change out the older style connector for the backup light on the 1989 MKIII R154 transmission sensor pigtail.
In this case the terminal ends were the same for both connectors. Only the housings changed. I think I took my old one off my SC300 5-speed harness.
Fitting the 2JZGTE ECU mounted sideways with the SC300 ECU cover
This was a puzzle for a short time. The 2JZGTE ECU is designed to mount sideways and the wiring length for it if left stock (LHD USDM harness, remember) won't let you mount it any other way even if you wanted to. I tried.
The brackets on the ECU had to be shifted just a bit from their original positions but you will be able to lock the hook end up top into the SC300's eyehole that is part of its OEM ECU mounting system and one part of the lower GTE ECU bracket will be able to fit into one screw hole down low that is also used for the ECU cover.
The trouble then becomes how the ECU cover is supposed to go in without getting blocked in the center by the thick bundle of ECU wires. You do not want someone slamming their shoes on the passenger floor and hitting all the sensitive wiring.
The MKIV TT's have a different cover (discontinued of course) and the Soarer covers likely won't work since they are RHD spec.
The solution is to take a ruler and a grease pencil and draw a straight line down the center on the underside of the cover. It's easy to see what part of the center of the casting protrudes deeper than the rest. This is what was hitting my ECU connector wiring bundles and it had to be removed.
I took a small metal saw and Dremel tool and carefully cut down all the plastic divider above that grease line. I worked slowly and carefully so as not to overcut. I made it totally straight and smooth before finishing. I had thought this would reduce the structural integrity but it doesn't seem to as the panel is so thick and reinforced.
That was enough to let the ECU cover safely clear the thick wire bundles in the middle of the ECU and ABS computer area.
Also, since I decided to go with the MSD Tach Adapter solution for my swap I put that unit just under the ABS unit with some double sided tape.
In the picture below from left to right the extra wires you see are:
--unfinished bundled up A/C Compressor Mag Clutch wire (this will be run to the driver's side footwell near the fuse block)
--connection for MSD Tach Adapter
--direct connector for O2 Sensor #2 that will go into the short custom-made extension harness to the factory #2 O2 sensor location on my Cali-Spec SC300 (which is to the left of the factory stereo against the trans tunnel)
Returning to an earlier post where I tried to find a suitable replacement for a big fuel type hose of a specific diameter at one end and another diameter at the other end for the 2JZGTE wastegate VSV, I did find a solution. It was right under my nose.
Refer back to this post for all the preliminary research:
I took the OEM Toyota hose P/N 23829-07010 for a 1999-2006 Toyota Tundra and realized all I needed to do was cut it off at the largest diameter end. Then I was able to connect to the big wastegate VSV near the water pump and the thick metal line up above the turbos. I used two clamps on both ends which were still available and common parts from Toyota.
This is an excellent replacement for part of the discontinued dual hose assembly. The smaller long hose that goes to the other VSV and upper metal line can be replaced with appropriate length Gates #27042 5/32nds vacuum hose.
Feb 2020 Update/Edit: I changed this hose yet again to a slightly tighter generic aftermarket vacuum hose I had laying around. With it I used a tighter Toyota OEM tension clamp: P/N 96132-51000. This hose seemed to fit a bit more snugly than even the replacement 99-06 Tundra hose listed above but probably isn't made of the same level of durable material. I'm still looking for a suitably strong/tough fuel-grade vacuum hose that can fit in for the discontinued OEM Supra TT hose.
I'll update this post when I take the sample cut of that hose and match it up with something of the same inner-diameter to better identify it.
SC300 brake booster to 2JZGTE USDM intake vac fitting
First of all, the torque for that intake manifold vac fitting bolt is MIA in the Supra MKIV TSRM. Looking at nearly every other major bolt that goes onto the intake manifold they all seem to require 20 ft-lbs. So with two (2) new crush washers (P/N 90430-12005) I decided to set my torque wrench for 20 ft-lbs and I torqued it down to that figure. I think that should be sufficient.
Now to connect that port to the vac booster I copied what I saw in another thread and used a new in-line vac limiter fitting (have to find the part number), four (4) new factory clamps (P/N 96135-41400) and some similar diameter hose. I just took my old brittle one into an autozone and sized the inner-diameter as close as possible.
This was purely a precaution and preventative maintenance on my part but when I inspected my old OEM driveshaft flex coupler it had some cracks. I've read that a couple of tiny ones are OK but mine had some very deep ones and I felt it was best to replace it after over 25 years of service.
Upon reinstallation I took care to put it in exactly the way the old one came out and to follow and maintain my grease pencil alignment markings. The bolts have to go in only in one direction.
Not pictured but the front MKIII R154 driveshaft section has to go on with four small nuts each requiring about 54 ft-lbs each. I was a bit troubled that I could not quite reach the full 54 ft-lbs since the driveshaft moved enough that I feared I was going to strip the nuts. They were on tight with plenty of torque but I am hoping that my efforts to keep what torque wrench application I could even will allow for safe operation.
I would say that my applied torque is CLOSE but perhaps not quite 54 ft-lbs for each of the four small nuts. If I were to guess I'd say they probably need to be replaced with new ones the next time they are removed.
Everything else was able to be torqued down exactly as dictated in the manual.
You will find torque specs for an MKIII R154 front driveshaft in the MKIII Supra Turbo TSRM.
Remember that if using the MKIII R154 front driveshaft you retain your SC center bearing but swap on the mounting flange from the other end of the MKIII R154 setup and mate the two together.
For reference, here are the torque load specs I was working from:
SC300 Driveshaft torque loads:
Propeller shaft center bearing to body — 36lb-ft torque
Intermediate shaft x propeller shaft — 54 ft-lb torque
rear prop shaft rubber to differential flange — 58 lb-ft (bolt heads inserted from prop shaft side, alignment marking required)
R154 MKIII intermediate shaft 4 bolts — 54 ft-lbs (these require alignment markings)
d/s Center brace — 9 ft-lbs
Trans crossmember torque loads:
crossmember x body — 18 ft lbs
R154 mount bolts — 18 ft lbs
Crossmember nuts — 10 ft-lbs
Crossmember bolts — 19 ft-lbs
Engine mount torque loads:
front engine mounting insulator X suspension crossmember — 43 ft-lbs
rear engine mounting member (Bracket) X engine mounting insulator — 10 ft-lbs
While many owners will say that this extra fan is not needed I feel it's important to add in for my swap. I've frequently had this car in very hot climates which can semi-frequently reach 100 degrees on some days. With the heat the twin turbos generate under hood I not only want a foolproof cooling system but a better guarantee that my A/C output will be cold.
Here's how I did it on my car:
First, I did a lot of research to figure out how to replicate the twin relay setup for the fan operation on stock MKIV Supra Twin Turbos. In a nutshell with the OEM TT system the sensor on the radiator isn't really a sensor but a thermal switch that completes one of the two relay circuits when the coolant temperature reaches 212F and does not cut the circuit until the temperature gets below 196F. It does this overlap in temp range in order to not constantly shut on and off.
The other relay in the OEM TT aux fan system is the A/C Mag Clutch trigger that completes the same overall circuit and triggers the first relay whenever you turn on the A/C function from the HVAC panel inside the cabin.
2021 Edit/Update: The other relay is a five-pin relay that is what actually feeds power from the 30A Fan fused circuit into the four-pin fan relay that feeds power to the fans. Further, that four-pin relay actually operates in the inverse of how a normal relay operates since all the radiator coolant temp "switch" *and* the A/C pressure "switch" do is keep the trigger circuit for the four-pin fan relay completed UNTIL one of them breaks the circuit (when the A/C pressure is high enough to break the circuit or when the radiator coolant is high enough to trip the coolant switch in that location to break the circuit from there).
As of 2021 I have recreated this OEM TT fan control system in my SC after finding all the necessary parts and finally understanding how the circuit actually works. I eventually switched to the Toyota Supra TT fan control setup after updating from the 93-96 TT single aux fan to the 97-02 TT dual aux fans and shroud plus an OEM Toyota Soarer Z30 1JZ-GTE Automatic condenser fan unit in front of the condenser and radiator (an MKIV TT Auto condenser fan will work the same way).
Since the small OEM pancake aux fan motors draw 4.5A each and the more conventional OEM aux condenser fan motor draws 8.5A (all on the same circuit path) that can be conservatively estimated at 17.5A continuous current draw when all three auxiliary fans are on. I don't like a conservative estimate though and I stayed with Toyota's intention of wiring the circuit to handle 30A if needed. This meant that keeping the power feed source and fuse close to the battery positive terminal and locating the relay and other wiring underneath the battery tray and slightly behind the headlight... just as it is with a stock 93-02 Supra MKIV TT.
For the bracket I got away with a Toyota 4Runner ABS relay bracket and zip-tying and electrical taping the two relays together temporarily... but the permanent solution is to use a fan relay bracket from a Land Cruiser 100 / Lexus LX470 1998-2002 and building a custom 90-degree L bracket for it to allow for a much cleaner mounting solution. This was needed since the MKIV TT fan relay bracket was discontinued by the time I did this part of my project.
12ga wires end to end would have been sufficient but I went with 10ga for the battery positive feed to the five-pin fan power relay, 10ga from the four-pin fan control relay to the fans and 10ga for the fans to the chassis ground at the driver's side fender. Overkill never hurts when it comes to electricity.
Refer to this post for details on that if you want to try it yourself:
But ultimately I realized that there was no need to go to all that trouble when a much simpler aftermarket universal system could be used. Chnk inspired me with this post from his thread: https://www.clublexus.com/forums/bui...ml#post9194714
So I bought the same kit from Mishimoto (Model #MMFAN-CNTL-U) with the 1/8" NPT temp sensor option.
This kit allows you to trigger the auxiliary cooling fan anywhere between 150F-240F with a small adjustment ****. It will control a total load of 25 amps MAX. The TT electric fan uses a 20 Amp fuse and relay on the Supra MKIV TT so it will fit well within that range. The sensor will trigger the system if the coolant temperature gets too hot and there is also an A/C override trigger wire.
To get the 1/8" NPT sensor to work in the original temperature switch location I ordered an Earls #9919AUJERL adapter:
The instructions were very straightforward. You just need to size up your wires and make sure you note the correct positive and negative terminals on the OEM TT aux fan.
The OEM TT Aux fan parts:
Wiring the system up and creating conduit wrapped in Scotch Super 33+ electrical tape. I also used some Weatherpak connectors to create a main disconnect point that runs through the firewall:
The firewall connections shown in this big Weatherpak connector are:
Pin 1 -- Custom 97+ Foglight harness relay wire to dash switch
Pin 2 -- Custom 97+ Foglight harness trigger wire from tapped parking lights to dash switch
Pin 3 -- VDO Oil Pressure sender wire (sender makes its Ground connection through the engine block) to VDO Oil Pressure gauge in cabin
Pin 4 -- Unused/future sensor/sender wire
Pin 5 -- Yellow +12V Switched trigger wire to Mishimoto Fan Controller relay
Pin 6 -- Green/Blue A/C override trigger from A/C Compressor Mag Clutch wire to Mishimoto Fan Controller relay
And here is the finished wiring I made under the dash to take the GTE harness A/C Mag Clutch wire through a protective conduit through a couple of single pole Weatherpak connectors to this green/blue wire that comes out at the firewall connection that leads to the Mishimoto fan controller.
I don't show the rest of the path but I put this small gauge wire into a protective sleeve and ran it all the way from the ECU/harness area past the stereo and tied up underneath the footwell area until it reaches another single-pole Weatherpak connector near the firewall bundle of wires.
EDIT: It ended up that I was incorrect about routing the Mishimoto fan controller override wire into the cabin to connect to that unused Supra MKIV "A/C Mag Clutch" wire (Supra II1-10). It really has no use whatsoever except to plug into the Supra's own unique "A/C Amplifier" unit which does not exist on SC's.
The solution to triggering the Mishimoto fan controller any time the A/C is on is to splice into the A/C compressor harness connector Pin 4 wire (which is what powers the compressor from the A/C magnetic clutch relay) or from the same wire at the EB1 connector, Pin 1 (which feeds into the A/C mag clutch relay at Pin 1). From either point along that wire a spliced in wire connected to the Mishimoto controller's override wire should allow the auxiliary electric cooling fan to come on any time the A/C is turned on.
Feb 2020 Edit/Update: Actually it turns out that I was right all along about this particular wire Supra II1-10. A lot of back and forth trying to figure out exactly what it does finally led me right back where I started. I still don't know exactly what Toyota intended it for in the Supra MKIV TT but for the purpose of being a +12V trigger signal that goes on and off with the A/C Mag Clutch and which can manually override an auxiliary cooling fan controller to turn on it is perfect.
Alternatively you can also pull the same A/C Mag Clutch on/off +12V trigger signal from the wire at the SC's EB1 connector, Pin 1 (which feeds into the A/C mag clutch relay at Pin 1... but I think this is easier if you happen to be starting with a Supra MKIV TT engine harness.
Also, if you're building your own custom harness or having it done for you adding this wiring connection to go through it is very simple: you'd only need to tap into that SC EB1-1 wire and run your +12V signal wire just a short distance to wherever in the engine bay you prefer to mount your aftermarket auxiliary electric fan controller.
But since many of us convert OEM Toyota 2JZ-GTE and 1JZ-GTE harnesses or buy Tweak'd or Panic Wire harnesses with standard-to-mostly-OEM-spec arrangement it may be that this signal wire is taken from different locations depending on whether or not you're starting with a stock Toyota harness or an aftermarket harness.
Note on the factory under-radiator pipe for the OEM side mount intercooler setup:
After a lot of cleaning a few weeks ago with degreaser I was able to save all of my used OEM IC hoses which were still supple after all these years. Stainless steel clamps varying from 3" Dia to 4" Dia were very inexpensive to replace. The piping just under the throttle body was annoying and difficult to install at first but the only issue I had was aligning the Supra MKIV TT OEM under-radiator IC pipe.
I soon realized that the problem was the Supra MKIV TT's SMIC has a straight exit to that thick round plastic pipe while the Toyota Soarer version accounts for a slight angle bend from the lower exit on its end tank.
Since I had both under-radiator SMIC pipes I used a spare OEM 45-degree IC hose (3" Diameter I think) to connect to the Soarer lower IC pipe and from there it's all the same hardware and path right into the throttle body. There is a marked visual difference between the MKIV TT lower IC pipe and the Soarer lower IC pipe but the inlet and exit diameters are exactly the same and other than the angle difference on the end that goes to the Soarer factory intercooler they do exactly the same things.
I didn't snap a picture or comparison but here's a snapshot from the EPC diagram for the Soarer's factory intercooler system:
Note that the shroud pictured is for the 1991-1995 Soarer 1JZ-GTE. The shroud I've put on my 91-95 Soarer OEM intercooler is from a 96-2000 VVT-i Soarer.
And here is the factory intercooler exploded diagram for the USDM Supra MKIV TT:
Oh man it's starting to look really good! seems like you were a busy bee with all the updates last night lol. What did you have left to work on, it looks like you have everything pretty much in place so far and just working out the kinks
Thank you! There are more upates to put up. I just got too tired continue last night.
These are all catch-up updates. At current time the SC swap is finished with the exception of installing the Supra TT Denso OEM fuel pump and getting it and the fuel ECU wired.
And the engine break-in upon first start.
I’m waiting on a gas tank siphon kit to be delivered and I’ve been studying both the TT Fuel ECU schematics and various guides for the 12V Fuel ECU Mod to figure out what to do.
Gotcha, looking through your thread you've really put a lot of detail into this project, I bet she'll run like a beast when you crank it up, and a reliably built beast at that. Looking forward to seeing you get this thing going!
07-03-18, 06:30 AM
