Billy305

iTrader: (2)

I have my 95 SC300 and next month I’m going to pick up a 2jzgte VVTi auto from an aristo. I’m slowly putting together and ordering parts but I’m a little confused on the cooling set up. From the engines I looked at I don’t believe they have a belt driven fan like my SC300’s does. Planned to buy an upgraded radiator as well like a mishimoto aluminum designed for a Supra tt. I ordered the brackets that will mount this radiator in to the SC300. Do I need to buy the dual electric fans and matching shroud from an aristo and if so will it bolt up to that radiator I plan to order? I also am ordering the external tranny cooler. I’d like to go factory as far as the fans go but I’m confused one which parts I need.

thank you

Billy305

iTrader: (2)

I also order factory Supra radiator hoses. I’m assuming this is correct?

KahnBB6

iTrader: (5)

Hey Billy,

The Aristo's with 2JZGTE's *do* use belt driven fans like the Supra MKIV and SC/Soarer. However with the Aristos they use a hydrofan setup very similar to the one the SC400's use (and I believe also similar to those found on stock Soarer 1JZGTE's?).

For your swap's cooling system to be "bolt in" with off the shelf parts you will need:

--An aftermarket Supra TT radiator of your choice (Koyo's aluminum or Mishimoto's aluminum are highly recommended)
--If you have an automatic transmission you will need to add an external auto trans fluid cooler since the aftermarket MKIV TT radiators come set up for manual transmission application only. Easy to get a Hayden or other external auto trans cooler installed.
--brackets to mount a Supra MKIV radiator in an SC (as you mentioned)
--Supra MKIV TT radiator hose (top) 16571-46150
--2JZ-GTE water pump 16100-49847
--Supra MKIV 2JZ-GTE / TT Fan (blades do not stick out as far as the 2JZ-GE fan blades and thus clear the top radiator hose)
--SC300/Supra NA/TT OEM fan clutch
--OEM SC300/Supra water pump pulley
--4x nuts to bolt fan clutch onto water pump pulley 90179-06159
--1993-1996 Supra MKIV TT fan shroud 16711-46160 (single hole for early style aux A/C electric fan)
--OR.... the 1997-1998 Supra MKIV TT fan shroud (holes for later style twin aux A/C electric fans)
--Lower fan shroud part 16702-46010 from an SC300 or MKIV Supra (clips for this are 90468-05109 x2)

Finally, I recommended you get a used 93-96 Supra TT OEM auxiliary cooling fan assembly to bolt onto your new radiator/cooling setup. This is not only helpful to keep your A/C running at optimum but it is also helpful to have it trigger on to help keep your coolant temperature that much more in check on hot days or after running the engine hard.

The 1997-1998 Supra TT twin aux A/C fan setup is better but rarer and harder to find and it requires the 97-98 TT radiator shroud to fit. I went with the 93-96 version and it's fine in my opinion. To control it on an SC I used Mishimoto's fan controller unit (model #MMFAN-CNTL-U) with the 1/8" NPT temp sensor option. This was WAY easier than recreating the great but much more electrically complicated twin relay setup that stock Supra TT's use for this.

I used an Earls #9919AUJERL adapter to screw into the radiator's sensor plug location and convert to a 1/8" NPT mounting area for the Mishimoto controller's coolant temp sensor.

To plug into the Supra TT OEM aux A/C fan I used:

93-96 Supra TT aux A/C fan connector — 90980-11237
Terminal repair wires (x2) — 82998-12480

Here's my thread post on how to get that installed and wired up:
https://www.clublexus.com/forums/bui...l#post10241327

And here's a thread I made a while back showing every little thing needed to fit a Supra MKIV style radiator into an SC including the 93-96 TT fan shroud. Just note that since this was written while I was still running my stock 2JZ-GE NA engine I did not at that time use a 2JZGTE upper radiator hose or 2JZGTE specific fan blade. And at the time I didn't have my auxiliary electric fan hooked up yet:

https://www.clublexus.com/forums/per...0-5-speed.html

It's pretty straightforward. Getting those radiator mounting brackets does save a few steps! If you don't mind my asking, what part number are those brackets and who makes them?

Billy305

iTrader: (2)

Thanks for being very detailed and listing the parts numbers for me.

for the fan clutch and pulley I can use the one out of my current sc and I just pop the new fan on?

the bracket I bought from Supra store but I believe it’s made by power house racing.

Ali SC3

iTrader: (10)

Yes, you can reuse your original GE stuff except for the actual fan blade and I think the plastic shroud is different. Khan's got it all up there.

also if you aren't 100% trying to use the gte parts etc.. you can go to an electric fan setup also like the is300 fans etc.. do a google search lots of options.

Billy305

iTrader: (2)

Appreciate the quick reply. I'm open to suggestions but my buddy who has built a few supras says he feels like the electric fans dont move quite as much air. I think im going to stick to as much oem stuff *** possible in this build. Great advice above from Khan as well, im not 100% why he had to go in to the cabin with AUX fan wiring other than to pull an ignition signal?

Billy305

iTrader: (2)

Im looking at these tranny coolers, which is recommended? Im guessing a passive without a fan would work fine but im not sure about the size.

https://www.mishimoto.com/catalogsea...mission+cooler

KahnBB6

iTrader: (5)

The reason one wire went into the cabin for the fan controller on my install is that the Mishimoto unit has two triggers to cut the aux fan on and off:

#1 and most important is the 1/8” NPT coolant temp sensor that goes into the bottom of the radiator. This is what should primarily turn on that extra cooling fan automatically whenever it’s needed

#2 is the fan controller’s “override” wire. This just needs any electrical signal directly from some source or relay or manual switch to tell the fan controller to turn the fan on.

For that override wire I wanted it to always activate when the A/C was turned on. Initially I rigged up a manual switch but got annoyed with that and finally figured out how to use an extra wire off my converted 2JZGTE engine harness that gets power when the A/C magnetic clutch is activated.

At least on Supra 2JZGTE harnesses it is a wire that does not need to be used when converting the electrics for an SC300/400. But it proved a convenient way to not have to flip a little switch each time the A/C was turned on.

I guess you *could* tap into the A/C mag clutch power wire off the little connector going onto the A/C compressor in the engine bay but personally I wanted to avoid cutting into factory wiring paths as much as possible.... and I already had a little bundle of wires going from the engine bay into the cabin anyway:

-fog light relay switch wire
-oil pressure gauge wire
-Mishimoto fan controller override wire
-extra wire for oil temp sender
-THICK 10ga wire from the battery all the way to the 30/40A relay up where the SC fuel ECU is located (I replaced it with a Supra TT fuel ECU in that spot) to provide direct power with a relay for the Supra TT Denso fuel pump on its own circuit.

And a couple of other wires I don’t recall the purpose of offhand without reviewing all of my electrical notes for my swap.

With all those other critical extra wires going into the cabin through the firewall it was simple to add one more small gauge wire to the bundle.

I don’t know if Aristo 2JZGTE harnesses have that extra A/C mag clutch wire on them but assuming they do I’d use it for this purpose.

Alternatively if you are doing your own engine harness conversion work and have the entire harness unwrapped you could just trace that one wire to where it begins and make it come out of the harness in the engine bay side with a little protective covering and an aftermarket WeatherPak/Delphi single pole connector. Then there would be no need to run it into the cabin firewall at all.

The way I did it with other necessary wires going through there anyway just seemed the easiest. And by then I had already wrapped up my engine harness conversion.

The big 10ga fuel pump relay power wire aside it is probably best to run all your planned accessory wires through your SC converted engine harness before wrapping it all up with harness tape. Then you minimize any “extras” that would need to be run through the firewall grommet later as afterthoughts.

But already my post is getting beyond the scope of that one wire into the cabin, lol.

Billy305

iTrader: (2)

Thank you for clarifying. I’m actually going to have my harness build by dr. Tweak. Maybe I can have them add something for this purpose.

Billy305

iTrader: (2)

Where did you mount your relay and fan switch unit?

Billy305

iTrader: (2)

What transmission cooler would you guys recommend? Im not sure if I need one with a fan and not sure what size is sufficient.

KahnBB6

iTrader: (5)

For mine I mounted it in a little spot in front of the battery behind the side of the driver's side front headlight. Hard to see in the second pic (and in these initial pictures taken during the installation I had not yet tidied up the wires as well as I would later) but you're looking for the big white connector with the bright green, red, white and black wires leading into it. That's basically where I left it. I did not mount it to anything as there are few such elegant (ie: flat) places in there to put it. So I left it in that easily accessible but still secure spot.

The extra universal relay unit you will also see there is not related. That's part of the DIY add-on fog light harness (using O.L.T.'s guide for non-foglight equipped 92-94 SC's + remote on/off switch in the cabin).




For transmission cooler ideas I would check Gerrb's big build thread. He's detailed some very good built A340E cooling setups with a couple of his SC's. I do think a fan cycled by its own relay controller and ATF fluid temperature sensor/sender is recommended.

I've got little experience with what is the best but the good auto trans cooler brands that I know of are Hayden and Derale.

Billy305

iTrader: (2)

Thanks!

Last thing. Im having a hard time finding the supra turbo aux helper fan and bracket because they are discontinued by toyota. I cant buy it new even if I wanted to spend the money. Any good ideas where I can pick one up?

KahnBB6

iTrader: (5)

Indeed they have been discontinued for a few years now. You're going to have to find the fully aux fan assembly used. Ebay or Supraforums classifieds. Or you could put a specific WTB ad in the MKIV Parts Wanted section on SF.

The little fan, motor and bracket should come as one piece. The harness side connector and terminal wires for it you can still order. Also, while the fan motor itself is a very durable heavy duty cycle unit that lasts many, many years it can still be replaced with a new part from Toyota. I traced the actual motor itself (not including the fan blade that goes onto it) as also cross referencing to a few years of the Toyota Prius. And that motor part is still in stock with Toyota.

But chances are you'd probably never have to replace that motor.