vigman

Ok I think I mis spoke I was saying buy a WHOLE SC-300 engine harness...
Our SC swap only has 2 O2 sensors 1 off the exhaust manifold 1 into the MAIN cat ( like all those pix's I asked you for ) ours has NO 3rd O2. The REAR O2 is part of the BODY sub harness and we had to make our own harness to go from the Supra wiring to the O2 by the trans tunnel.

Not Mallory ( I mis spoke ) MSD....

As far as the correct sender... YES we could get the gauge to go up and down but it was not ACCURATE...
and all the conventional " wisdom " of hacking the dash or adding a resistor is series is just dead WRONG...

We have 2 clusters that both work except most needles are burnt out....for the led lighting.

1) The R value of the SC is different than the Supra and the " ramp " is different.
2) David didn't want to open up the hole where the Supra temp sender was and add a bung for the SC thread size.
3) The OTHER plan was to add an inline adaptor on the upper hose, with the correct thread size for the SC sender.

But with all that ... the " stock " gauge is not " calibrated ".. so we went with a aftermarket gauge.

That is why we side stepped whole gauge thang

KahnBB6

iTrader: (5)

Mike, we're on the same page. I'm looking for an entire 92-94 SC300 engine harness (manual or auto). Not sure if it being Federal or Cali will matter at this point.

Whatever you've done with your GTE harness is what I have to do. So...

I double checked my turbos and #1 TT OEM cat (which has no O2 sensor bung). Plus Rockauto lists only *two* O2 sensor locations (upstream and downstream).

Anyway, I know the body sub harness you're talking about. It's basically a long extension on the Cali SC300's. I can't remember if your son's 1992 SC was Cali or Federal to start with.

I copied down your notes in Post #12, Page 1 of your swap thread to look over.

What doesn't make sense to me is that if the Supra TT's all used rear O2 sensors on the main cats anyway, why wouldn't they use a near identical body harness like the Cali SC300's? They're nearly identical cars.

I must be confusing something, still. And it's late.

...

Ah, okay. Understood on the MSD. I'll be using the same thing then for the tach fix

...

Regarding your cluster needles, Mike... whatever you do DON'T send them to Lextech Lighting. Those folks are known to lose or break clusters.

If you want to get those needles restored, everyone here seems to universally recommend Tanin Auto Electonix now. They have a good reputation for repairing our SC instrument clusters properly and in a reasonable timeframe.

...

I have a good understanding of the SC dash engine temp gauge issue with this swap now. The gauge responds differently. Thank you! So your solution WAS going to be swapping the Supra GTE temperature sender for the SC temperature sender with an adaptor?

But... when you also say that the SC's factory gauge isn't calibrated, did you mean that from the factory on a stock SC300 drivetrain it's still not properly calibrated? Or do you just mean in terms of one of these swaps including your GTE to SC sensor swap solution it still wouldn't have read correctly?

First I've heard of this on a USDM swap vehicle. I guess no one else has posted these details.... frustratingly.

A light bulb just went off in my head and I was about to suggest,"Hey! What if I were able to buy a gauge from a 1JZGTE Soarer and swap that into---"

At which point I remembered it's a completely different cluster

I think I'd like to get my SC dash temp gauge to work in the most basic sense if possible, but I guess I will be wiring in an aftermarket temp gauge like you.

Ali SC3

iTrader: (10)

I had a ge head that I was trying to stick gte coolant sensors into because thats what I had ordered thinking they were the same (there is one sensor for ecu (2 wires) and one for gauge (1 wire)), and I can tell you that the one for the gauge was not the same size threads on both heads, but the one for the ecu I want to say was the same between the 2. I would think that the gte one is close enough for the sc300 as there are tons of swapped cars with working coolant gauges, might sit a hair higher or lower on the gauge but the stock gauge is pretty inaccurate anyways. it was my understanding the ranges are similar on most all toyota clusters, so maybe the sensor was bad.

vigman

The 2nd cluster is a test cluster for my MAD SCIENCE.... so it will never see the road again...

The original sender works OK ( on the bench ) and measures correctly with boiling water / vs resistance... and the resistance with the smaller sender is OFF......

Probably ok for most peeps ( about 40 degrees off at operational temp. ) .. I just wanted something with actual NUMBERS.. ( ODC ) ..

If was MY CAR I would have the hole machined to accept the SC-300 sender ( single wire ) While you were getting the head work done...

Remember OUR CAR PASSED CALI SMOG ***** WITH 2 O2'a, and if memory serves the ECU won't support a 3rd.

Our car was an AUTO in it's previous life , and it was a CA car....

KahnBB6

iTrader: (5)

Just getting back to this.

Thanks Ali and Mike. Given what you've both clarified I understand now. I'm reluctant to machine the GTE cylinder head given how rare it is. An adapter setup as you suggested, Mike, I would do, but I got the impression that you'd have done that already if you thought it would be adequate. 40 degrees off is significant but as long as I can tell a rough safe operating range from the factory gauge I'm fine with that.

My real solution will be similar to yours but rather than use a physical gauge I am going to hook up a second engine temp gauge function to the LXCC climate controller I bought. This will accompany several other digital gauge input signals I will run through it:

-Boost (PSI or BAR)
-EGT
-Engine coolant temp (secondary to factory dash engine temp gauge)
-Volts
-Outside temp
-Side Intercooler surface temp (I will be installing a separate surface water spray system also)
-Oil pressure
-Fuel Pressure

You are 100% correct about the USDM 2JZGTE ECU not supporting a third O2 sensor. It is just one on the turbo cast section and one on the second ("main") catalytic convertor. I think I had some mental catchup to do here as I tried to follow but my mind was partially divided elsewhere.

One thing I definitely would like to do, when time may (or may not) allow, is to show you the 2JZGTE harness I have and confirm that one aspect of the SC300 harness blending into the GTE harness that you were speaking about.

And thank you for clarifying the origin of your son's SC! Cali spec was the important part I wanted to know. It also informs me that I should mirror your general approach with the wiring harness conversion, though I'm still confused about the 6-speed "Federal" harness you say you have... except for one thing that occurred to me:

You may have been sold a 1998 USDM 6-speed harness since it was within the last of their new old stock to sell you.

This would be significant because for the 1998 model year there was NO 6-speed TT Supra offered for sale in California due to yet another emissions hurdle. In ALL other states for MY1998 you could buy a 6-speed TT.

I should have taken down notes but I found that there were at least three different variations of the USDM 6-speed harness in Toyota's system. If I had to guess, I think they mainly pertained to: OBD1 93.5-95, OBD2 1997 (no USDM 6-speed TT in '96 in ANY states), and 1998 for 49-state emissions only.

vigman

IF memory serves it was a 95 harness. Yes would love to chat about wiring.
BTW
IF you will run a boost controller and it is seen by the REF's INSTA FAIL..

We had the BOX in the back of the car, and got a lecture….

Ali SC3

iTrader: (10)

Vig do you guys run the spring mod? you should check it out its evolved a little bit, and doesn't look like a boost controller at all.

vigman

David changed up the turbo controls a few times… not sure about the SPRING MOD ?/

KahnBB6

iTrader: (5)

Just returning to the last couple of posts now. I've had some other car issues recently that I've been trying to sort out before resuming with the project.

Just for having the box in the trunk? How long did that lecture last?

Currently a boost controller is a luxury item that's not in the initial swap budget. I do have a Greddy boost cut controller but I will not be installing that until later. Just getting the swap up and running in stock form will be enough of a triumph.

However... you do make me wonder if they will give me a lecture over installing the LXCC touchscreen controller where the standard HVAC unit is located above the radio. That is primarily a touchscreen HVAC replacement but it does have a virtual gauge display function which I intend to use (maybe not at the time of the BAR inspection for obvious reasons) and it will have a boost controller function.... which I may or may not use since it probably isn't ideal for the sequential turbos anyway.

Regardless, I think I've seen a picture of a turbo on one of the LXCC's menu screens. Even if the software isn't available to make use of that screen yet I wonder if the turbo graphic on that menu by itself would garner an overreactive "insta-fail" or lecture.

I don't feel like risking it but I might like to have the screen installed by that time and perhaps some pre-wiring run for some of the gauges I want. Maybe even that is just asking for trouble from them.

From me, they'll be getting a 100% stock car anyway. The fun toys aren't in the budget.

A chat or meet up won't be possible for me until we're into the new year but I'd love to if you're up for a brief chat again. No matter how I handle the harness conversion I need to fully understand what you had to do with the SC harness merging. Until the last few posts, I had thought only the SC body plugs needed to be swapped over appropriately... for THIS type of stock harness conversion.

I know what Ali is referring to. At least from having studied the Stu USDM GT28 Hybrid thread and the way SpeedForSale offers options for the conversion.

I don't know how stealth it really looks or not but it doesn't seem to be very complicated. It takes the standard wastegate from a normal boost pressure range of, I think, 10-14.5 or so PSI to a standard of 15-20 or so PSI. Something close to both those ranges. My numbers are probably off. A boost controller isn't needed for this.

However, I wouldn't do it with stock twins which won't do over 18 PSI for very long. STU Hybrids will. But most people running those are getting at least 93 pump gas and most are converted to E85. A few with weekend only cars will run a 100 octane fuel like VP100.

Also, I've read in at least a couple of places that 15PSI is about all we'd want to run on Cali's 91 pump gas. Maybe 16PSI at most. The stock wastegate spring is good enough for that as is.

Although Mike, if you and your son want to have some expensive kicks, you can get 100 octane VP100 for about $10/gallon at a little 76 station in Pasadena. Genuine street legal, catalytic convertor friendly unleaded race gas. I'll dig out the address if you like. It's one of only two places in the L.A. area that sell it, to my knowledge.

But a conversion to E85 with a flexfuel ECU, bigger injectors and a bigger fuel pump (and probably those pricey STU turbos) would still be a FAR more affordable way to run race-grade fuel.

...Not that E85 is a realistic option here anyway.

KahnBB6

iTrader: (5)

Minor update:

A week ago I received a Popformance LXCC controller. Very excited to get it working. I have some custom harness work ahead of me to pre-wire the eight gauge inputs. I'll be using a combination of quick disconnect Molex inside (9-pin connector I think) and tough WeatherPak universal connectors inside the engine bay.

And then I'm looking into locating the part number for the critical body harness connector that goes into the factory stereo because I want to keep my OEM pioneer and use a Metra connector to create a patch harness to connect everything. I don't like splicing into original wiring unless I have to

Update: I've ordered a Metra 71-8112 Reverse Radio Harness which plugs into the back of the OEM Pioneer stereo (intended to restore the factory harness in case it's been hacked up). I will use that with the other Metra harness I have with the female connector.

I'm excited for this but I came across this thread which gave me some pause regarding smog and/or BAR inspection when it comes to any kind of gauges.

Vigman, do you have any thoughts, since you hooked up at least one aftermarket gauge for your swapped USDM GTE car? In my case I will have no physical gauges (it all displays on the HVAC unit) but there will be aftermarket sensors for all of the functions:

-Boost (PSI or BAR)
-EGT
-Engine coolant temp (secondary to factory dash engine temp gauge)
-Volts
-Outside temp
-Side Intercooler surface temp (I will be installing a separate surface water spray system also)
-Oil pressure
-Fuel Pressure

http://www.allfordmustangs.com/forum...-fail-wtf.html

And...

http://californiafords.com/cgi-bin/u...=6;t=018857;p=

Edit: based on the last one I will look this up. I may actually have an issue at least connecting sensors for boost pressure, EGT and fuel pressure since they would all directly be part of the emissions controlled parts of the vehicle.

Maybe those are things I can hook up long after the project is finished, since I still won't be using physical gauges.

Very annoying, however...

....


For the swap specifically I've taken delivery of some miscellaneous new clamps and hoses for the twin turbo VSV side of the car. Labeled those in the appropriate parts groups for now. Will speed on up the rest later...

vigman

To answer you gauger question...
In the pod
Vac/Boost
Volts

In the center console
Water temp

David's car DIED last week ( electrical gremlin ) ...
No signal to the fuel pump controller module.

It's pointing to the ECM connector... we found some pins that had slightly backed out from the shell.

And this was a NEW 1300.00 harness !!!!!

So after pulling the E 10 connector and re working it...
The car RUNS ... IF you jump the controller out and have 12 volts to the pump all the time..


We are still not getting the FPU signal off pin 22 ( i think ) off the ECU...

And we have a 2nd known good ECU...

I was brought in late to the " problem solving " ....
I think an external signal the the ECU uses to switch form 2.5 volts out to 5 volts out on the FPU line is missing.. like maybe TACH...

More to follow....

KahnBB6

iTrader: (5)

Mike, thanks for the gauge info-- BAR ok'd all of those when you and David took it in? When I get this LXCC wired in properly (I'm waiting on a Toyota splice electrode to come in for my OEM stereo "patch harness") I will be set up to run seven 0-5V gauge sensors with my readouts on the little screen. I will only be running the quick disconnect prewiring for them into the driver's side fender well for now.

The pin and ECU issue sucks! Yes, that also surprises me with a brand new engine harness.

With the known bad ECU, try sending it in to Tanin if you suspect it may have generated a fault. They say they don't get many Supra ECUs but that they would inspect and perform any repairs to mine if I sent it in, and I plan to very soon. Note that if you do, send it insured, don't use any overnight service and request an adult signature upon delivery both ways. They're good but I mention this because I had a bad experience with Fedex recently losing an ECU under odd circumstances.

I think you may have already covered this in a previous conversation with me but you are you running the Supra TT Fuel ECU and the extra EFI2 wire it requires... or just the SC300 Fuel ECU with the +12V bypass?

Ali SC3

iTrader: (10)

the "spring mod" I am referring to makes the first turbo spool to a higher psi under 4k rpm's. there are a few different spring mods.
you do this on the other wastegate as one wastegate controls max boost, one controls the spool on the first turbo.

The 2jz spools up the first turbo fast, so normally the first turbo will spool to X psi rather quickly and will hold that psi to like 4k rpm (power levels off till you reach 4k rpm), then ecu will let the second turbo come on and the boost raises to its max wastegate setting.

So when you do spring mod the first turbo will spool to a higher psi before 4k rpm's and with the right spring it will basically seem like there is no pause at 4k rpm's as by the time the first turbo reaches its higher boost setting, you probably crossed 4k rpms and turbo 2 has already come online making it seem alot more linear.
It just seemed odd to me that the first turbo would be set at such a low psi and pause like that. lots of people have discussed the issue on SF, they have a spring mod thread there but the version I am referring to is towards the end of that thread with pictures.

Ideally you want a bosot controller on one for controlling max boost and add the spring to the other to make turbo 1 give you a higher max boost.. and a healthy set of twins.

KahnBB6

iTrader: (5)

That's a much better explanation. Thanks, Ali!

My understanding has been that in 100% stock tune at the factory 10.5psi a set of USDM 2JZGTE twins can last as much as 200K or so, depending on driving style. It's supposed to be a very kind transition to the 2nd turbo at stock psi. Past stock boost not quite as much. The STU Hybrid twins are supposed to be much more durable regardless of boost potential.

Once the boost goes up the 2nd turbo tends to get hit harder in sequential mode from full-off to instant-on at 4,000 RPM. The danger threshold above 18psi on stock/non-upgraded turbines can be looked at as a separate limitation.

Are some versions of the spring mod generally thought to lessen the wear on turbo #2 when you up the boost? That's kind of what it sounds like from your description. Everything wears but anything that can smooth out that transition is a good thing.

vigman

We are running the stock Lexus setup ( with a SUPRA pump ) right now the fuel pump controller is bypassed so full 12 volts to the pump all day long. It's REEALLY noisy ( fuel in the lines pumping round ) no the pump itself.
Currently David is just FRUSTRATED with the car… so more … later