xspsi6

iTrader: (31)

I know this has been done in a is300 before but I can not find any info on it
Here is what he had from what I remember...

Aristo motor 2jzgte vvti
Stock wire harness
stock a650 trans
stock multiplex ecu
Aem fic and injectors plus a walbro pump
Everything that was attached to the engine was stock including all the sensors etc
So basically the only thing he had was an aristo vvti long block and intake manifold he even was running the stock dbw throttle body so everything worked like stock even the traction control however I can't find it for the life of me when searching so my question is has this been done on a 2gs with a multiplex ecu before?

I am trying to remember the guys user name but can't for the life of me recall

xspsi6

iTrader: (31)

I found him and this is what he said about this very question.....

Hello,
We are about to start on a VVTi Aristo swap into a 2001 IS300 for a customer. I have been reading through this thread to get some information on what other IS owners have done, and I think I might be able to clear up some of the persistent questions that people have regarding why you would use the JZS161 Aristo VVTi engine, what ECU to use, trans, etc.

So why not use the complete JZS147 Aristo or Supra 2JZGTE, ECU, wiring harness and trans like you would on any other engine swap?

Sounds like the best way to go right? Transplant the entire running setup just as the Toyota Gods intended? There is a catch: The IS300 was the testbed for a new "serial computer link" system between some of the computer modules in the car. In theory, this should make complicated cars like this have less wiring. Just like USB for computers, the Toyota "Multiplex Communication System" makes integration of the various modules tidier. It links the Engine ECU, body ECU, Theft Deterrent ECU, AC control, and dash among others. So in short, the IS300 ECU feeds serial data to the dashboard for engine temp, oil pressure, etc. It feeds various signals to the A/C module necessary to make it function. Without the IS300 ECU in place, these systems will not function correctly.

So, what can you do to get around this? People that simply turbo charge the factory GE engine simply leave the factory ECU in place and use a variety of methods to get the newly boosted engine the correct fueling and timing. this can be as simple as a rising rate fuel pressure regulator, (and properly constructed return fuel system conversion) or more complicated methods such as piggyback fuel controller. AEM FIC, Emanage, etc. Some even experiment with full standalone systems, but feed the essential wiring to both units to allow the factory IS300 ECU to "think" it is running the show but really it is just controlling the auto trans, feeding info to the gauges etc. Some of these strategies are better than the other, more or less likely to set CEL's etc.

So how does that relate to installing a full twin turbo GTE in the IS300, and why would you want to use the VVTi JZS161 Aristo engine?
Because of how intensely integrated the IS300 ECU is in the car, it is very difficult to take it out of the equation. What many people doing the GTE swap have come up with is this: Leave the IS300 ecu in and let it control the new GTE engine, add piggyback fuel/ignition as needed to control the engine. That leads to the next question, isn't the IS300 ECU going to totally freak out? How can it control the Aristo trans, won't it set a CEL without VVTi solenoid present, what about the 6 coil packs on a GTE, et?. This is why people prefer to use the JZS161 Aristo engine, it is the MOST SIMILAR to the IS300 GE engine. It has all the VVti hardware present, cam and crank signals match up, etc. You can simply remove the GTE wiring harness, and use the IS300 GE harness and ECU.
Well, not SIMPLE, but it gets us a lot closer than trying to "fake" all the Multiplex Communication signals, deal with having 2 full ECU's in the car and the resulting wiring nightmare, or live with multiple CEL's that you cannot get rid of! Not to mention the other systems that will need input and control from the IS300 ecu like the evaporative emmisions system. The JDM ecu from the JZS161 GTE just does not have the ability to control the evap system. It also makes transmission control a breeze, as long as you retain the IS300 transmission your car came with. It will most likely need to be fortified to take the greatly increased torque. This will also allow you to use the factory driveshaft for the IS.
So, what does the IS300 ecu not do that the GTE engine needs? Well for starters there are quite a few VSV's in the twin turbo system that will not be connected to the IS300 ECU. These are mostly to control and sequence the sequential turbos. They can be carefully removed and run in "true twin" mode. This also involves wiring a flapper or two into a set position. This is NOT the wastegate, but rather the valve that sends all exhaust into one turbo. Another thing the IS300 does not do is connect to the MAP sensor (turbo pressure sensor) mounted on the VVTi GTE intake manifold. On the JDM engine this is the main engine load sensor that fueling is calculated from. On the IS300, this is done with the MAF (mass air flow) sensor. You will have to integrate the IS300 MAF into the intake system. The IS300 ecu is also not able to correctly fuel the turbocharged engine, and this is where you will have to get creative in selecting a piggyback ECU or fueling method. Ask ten different tuners and they will have ten different "favorite" methods or brands to do this! It is probably more important to find a system or method that your tuner is comfortable working with, than the "best" setup. If your tuner knows nothing about AEM, and everything about Emanage, that may be a better way to go!
There are a ton of other details that need to be taken care of to execute a successful GTE swap, but this will hopefully answer some of the questions regarding a main ECU/engine strategy, and why the VVTi GTE is the clear choice over a Supra/JZS147 Aristo GTE engine.

Cheers!
Carl Crawford
speed-source.net

xspsi6

iTrader: (31)

Ok I talked to Carl today and it appears what I said has been done by him more than once so I will report as I gather more info

tnjayhawk

My son's IS300 Engine retired prematurely because my daughter over heated it. So unfortunately we have to replace the engine.

Since we have this opportunity I was trying to find information on swapping the 2JZGE with a 2JZGTE. From what I've found it looks like the Aristo engine is the less problematic switch than the supra especially since the IS300 is an Automatic.

Any helpful information would be appreciated.

Am I correct in my assumptions with the Aristo vs. Supra engine? I believe all the true Supra engines are for "manual" transmission.

Can I run my stock IS300 Automatic Transmission?

Other than the motor are there other costly requirements to switch to the 2JZGTE Aristo?

Thanks,
Cedric

nuturf87

How about running a megasquirt3x retaining the stock GE ecu to control all those sensitive body control issues. Remember that megasquirt is only in control of timing and fuel. megasquirt only controls the engine portion of the ecu no body portions, thats why the stock ecu stays in place. Sorry to get off topic..lol