2JZGE Na-T TT Ecu Mod
02-15-19, 10:31 AM
#3766
You should be able to squeeze a few more psi out of that, till you get to the mid 11 AFR range.
At 10 AFR you might have some carbon buildup issues if you don't drive the car enough out of boost.
I would recommend going with at least a 275 in the rear and eventually going lsd.
255 def won't cut it without a lsd and if you spin that open diff too much it may eventually go.
At 10 AFR you might have some carbon buildup issues if you don't drive the car enough out of boost.
I would recommend going with at least a 275 in the rear and eventually going lsd.
255 def won't cut it without a lsd and if you spin that open diff too much it may eventually go.
02-15-19, 03:04 PM
#3767
You should be able to squeeze a few more psi out of that, till you get to the mid 11 AFR range.
At 10 AFR you might have some carbon buildup issues if you don't drive the car enough out of boost.
I would recommend going with at least a 275 in the rear and eventually going lsd.
255 def won't cut it without a lsd and if you spin that open diff too much it may eventually go.
At 10 AFR you might have some carbon buildup issues if you don't drive the car enough out of boost.
I would recommend going with at least a 275 in the rear and eventually going lsd.
255 def won't cut it without a lsd and if you spin that open diff too much it may eventually go.
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LEXXIUM (03-07-19)
03-18-19, 04:43 AM
#3770
I have read probably 80% of this thread. Was hoping to not have to ask redundant questions but I haven’t found clear answers to a few things. So I have a 99 sc and was wondering if the pin out for the vvti aristo ecu has the same layout for ignition. Also know that on post one Ali sc3 mentioned for these later models you need to use a gte maf along with the map and iat sensors. Was wondering if that has been tested and still runs well considering it wouldn’t be full speed density setup. From my understanding the way you wire in the map sensor at the ecu it takes the place of the maf sensor which wouldn’t make sense for me as I’d have to utilize both from what I gathered. Also have read on here that the tach would already work for my setup because I have an igniter wired in from factory. And about the vsv for the fpr plus the air assisted injectors that was mentioned for the 97 models I didn’t know if that was also used on the 98+ models or not. I know I’ll be needing the obd1 lower runners for the 440cc injectors and that sort of simple stuff mentioned many times throughout this thread. Just was hoping I could have some stuff cleared up about the later models if y’all have gotten any new insight over the years. Also I know the later models have thinner rods and can’t handle as much but i figured it would be fine below 400whp as I’ve already swapped in a mk3 r154 so that won’t be another hurdle for this setup. Thanks in advanced for any help this thread is awesome & feel free to correct me of anything.
03-18-19, 08:46 AM
#3771
Yes, they have the same basic pin layout. You leave your stock maf connector as is, just replace the stock maf with the gte maf.. it will plug right in.
The map sensor you wire it separately, 5v and sensor ground go to same place as TPS does at the ecu or splice into tps by engine, and signal wire you have to run to the ecu to the right pin.
This is mostly for boost cut on the 2jzgte vvti ecu as well as controlling the stock twins. you don't need this but to keep ecu happy you may need to install the map sensor. it will run with just the maf though.
For the air assist I would get rid of all of that stuff and use a non vvti lower runner and obd1 style injectors, the vvti gte ecu might control the fuel pressure vsv, but the air assist stuff is not necessary and will complicate stuff cause injectors are harder to find.
yes the later vvti 2jzge has weaker rods, you can run low boost but its not ideal. I would try and find a clean obd1 non vvti 2jzge engine locally and build another setup on the side that can support more power, or if something happens to yours.
The map sensor you wire it separately, 5v and sensor ground go to same place as TPS does at the ecu or splice into tps by engine, and signal wire you have to run to the ecu to the right pin.
This is mostly for boost cut on the 2jzgte vvti ecu as well as controlling the stock twins. you don't need this but to keep ecu happy you may need to install the map sensor. it will run with just the maf though.
For the air assist I would get rid of all of that stuff and use a non vvti lower runner and obd1 style injectors, the vvti gte ecu might control the fuel pressure vsv, but the air assist stuff is not necessary and will complicate stuff cause injectors are harder to find.
yes the later vvti 2jzge has weaker rods, you can run low boost but its not ideal. I would try and find a clean obd1 non vvti 2jzge engine locally and build another setup on the side that can support more power, or if something happens to yours.
03-18-19, 09:40 AM
#3772
Okay, awesome so I’d be in the same boat as the 97 model guys on here. With wiring the 2.3 map off the tps. Just don’t have to wire in the coils. So does the gte maf already do the job of the iat or would I also need to wire that in as well. Would the gte maf throw a misfire fit like the usdm guys run into or is that not an issue with the jdm maf setup? And the map pin at the ecu would still be the original 66 to 62? If so do I splice 66 into 62 or is it empty there. I’m eventually gonna pull the motor and build it. I just didn’t wanna test the waters on a fully built motor and hope I don’t cost myself BIG money if I messed up somehow. I’ve tried to source a pre 97 locally around here(Houston) but I haven’t had much luck it’s all gte motors that’re all a big gamble. Plus I’d have fun with 300ish hp for a while until I can throw some real money at it. I think it could handle it with the perfect tune you’ve given everyone.
Last edited by Sc3rrt; 03-18-19 at 09:50 AM.
03-18-19, 10:54 AM
#3773
They sell adapters now that you can drop into the vvti fuel rail to adapt to 14mm injectors. I'm not sure if they were around when I tried using the obd2 stuff. Seems like a better option for the air-assist lower people.
03-18-19, 12:51 PM
#3774
That’s a good option I recall seeing someone on youtube use them. Id just be scared they would leak. It would be something to look into for sure if they were reliable. Appreciate it though, did you ever get everything running good on your sc? You were the one doing the usdm ecu on here correct?
03-18-19, 12:52 PM
#3775
Okay, awesome so I’d be in the same boat as the 97 model guys on here. With wiring the 2.3 map off the tps. Just don’t have to wire in the coils. So does the gte maf already do the job of the iat or would I also need to wire that in as well. Would the gte maf throw a misfire fit like the usdm guys run into or is that not an issue with the jdm maf setup? And the map pin at the ecu would still be the original 66 to 62? If so do I splice 66 into 62 or is it empty there. I’m eventually gonna pull the motor and build it. I just didn’t wanna test the waters on a fully built motor and hope I don’t cost myself BIG money if I messed up somehow. I’ve tried to source a pre 97 locally around here(Houston) but I haven’t had much luck it’s all gte motors that’re all a big gamble. Plus I’d have fun with 300ish hp for a while until I can throw some real money at it. I think it could handle it with the perfect tune you’ve given everyone.
I am not sure about the misfires, if everything is setup correctly it should be alright but I haven't done it yet to say for sure, I am planning on doing one this year so I will let everyone know my experience then.
So far I haven't heard too many complaints about it but I would assume it wont run as perfect as the map sensor obd1 non vvti version of the mod. With everything setup right and the BOV recirculated properly like stock, it should be close.
66 and 62 refer to the pins for the non vvti ecu, remember the vvti ecu's use a whole different harness. If you are using your vvti sc300 harness, there wont be a pin there already.
you should familiarize yourself with this aristo vvti ecu connector before you even get anything started. it is the same connector as the 98+ vvti 2jzge connector and most of the pins are similar.
look for the "PIM" or Pressure Intake Manifold (MAP Sensor)
http://wilbo666.pbworks.com/w/page/4...ngine%20Wiring
You can also check out Gerrbs wiring thread there is alot of good info in there, and he just did a vvti na-t swap as well. DO not spam Gerrb, but read his thread and then follow up with any questions.
I don't get half the stuff you are writing, you said low boost on stock vvti block, then test the waters on a built motor?
I would think you would know how well it works or not after testing it on the stock block. regular vvti motors can be found all over the place for cheap.
The vvti gte ecu is probably not going to be as perfect on na-t with the maf as the obd1 map sensor setup, but it should be close.
I am not sure how far along you are, but if you are going the na-t route and doing it with a vvti setup, nothing is going to be straight forward, it for sure wont be easy, and issues will come up, so plan for extra time.
you will also need a sc300 vvti harness if your car isn't a sc300 vvti already, you didn't mention what the car was.
depending on what your car is, what you have already, and what you want to achieve I would maybe considering gte swapping it.
03-18-19, 01:58 PM
#3776
That’s a good option I recall seeing someone on youtube use them. Id just be scared they would leak. It would be something to look into for sure if they were reliable. Appreciate it though, did you ever get everything running good on your sc? You were the one doing the usdm ecu on here correct?
03-18-19, 05:19 PM
#3777
Sorry if that was unclear and jumbled up Ali my first post I mentioned I have a 99 SC300 stock vvti motor. I had asked if the ignition wiring for the vvti aristo would match my 99s harness considering I already have COP ignition. My main concern was that the aristo vvti ecu had a completely different pinout in comparison to the non vvti map only based that this thread mainly uses. I was hoping to use the information here thinking Vvti wiring and non vvti may be similar enough to piece it together. What I was saying about building the motor was that since I have a later model vvti SC that it has the thinner rods and doesn’t hold up like the 97 and older blocks do. So I wanted to test the waters on my stock block rather than a built one Incase I screw up. Thanks for pointing out geerbs thread as well. The reason I even left a reply on here was to make sure the 98+ models werent the same layout based in this thread. I saw there were a few 97 models that gave me a little hope even though I know they’re non vvti with a distributor. Also this is my first time I’ve ever had to post on here because my questions were always answered on here lol. Didn’t even have an account I read about 200 pages on here before posting and I have to say you gotta be the nicest guy ever to keep up with every question asked for almost 10 years. That’s gotta be some kinda record. I won’t ask questions on geerbs thread unless i feel like a have a good understanding. Thanks again tho y’all are the nat gods lol
03-18-19, 05:36 PM
#3778
Got it running enough to pass NYS inspection, which is basically just no codes in the ecu. It was pretty temperamental to say the least. I'm now running the JDM ecu and not looking back. I would also like to note neither the USDM or JDM ecus worked properly with the air-assist IACV, but that could just be 97 year specific issue.
03-19-19, 07:57 AM
#3779
wow you have been reading the thread for quite a while lol. good to see you post up.
The vvti 2jzgte ecu will plug right into your 99 sc300 harness, mostly everything is in the same spot except for a few minor things. I think gerrb had them mapped out in that thread.
the ignition is in the same spots, the maf, all the major stuff. from memory the vsv's are probably different between the 2 motors, so you might need to clean up the vacuum routing and get rid of the ones that are different, like for the intake butterfly ACIS etc..
so mostly plug in ecu, plug in maf, install larger injectors, delete air assist stuff or use the non vvti lower runner, and it should start and run with the maf on the engine right.
make sure to get the ecu without the immobilizer, you can tell cause there is an extra plug that is blank on non immobilizer ecu's.
in that link above, its the blue plug on the right. if its there its an immobilizer ecu which you do not want, if it is blank and just the metal ecu case there, its a non immobilizer that will work with swaps
http://wilbo666.pbworks.com/w/page/4...ngine%20Wiring
It is possible the maf setup can give us issues again, but for factory vvti control I am not sure how to avoid it just yet.
I am hoping the maf tune has evolved a bit more on vvti as even the 1jz vvti uses a maf setup (1jz vvti has no map sensor even cause its single turbo).
Unless someone learns how to control vvti individually, or going to a standalone, the best bet is probably the maf setup in conjunction with a piggyback like the aem fic which can use a map sensor and take over fueling etc..
its complicated but I figure worst case an aem fic or something similar would probably get it to work right. how bad can it be lol., there is no obd2 anyways with the vvti gte ecu.
The vvti 2jzgte ecu will plug right into your 99 sc300 harness, mostly everything is in the same spot except for a few minor things. I think gerrb had them mapped out in that thread.
the ignition is in the same spots, the maf, all the major stuff. from memory the vsv's are probably different between the 2 motors, so you might need to clean up the vacuum routing and get rid of the ones that are different, like for the intake butterfly ACIS etc..
so mostly plug in ecu, plug in maf, install larger injectors, delete air assist stuff or use the non vvti lower runner, and it should start and run with the maf on the engine right.
make sure to get the ecu without the immobilizer, you can tell cause there is an extra plug that is blank on non immobilizer ecu's.
in that link above, its the blue plug on the right. if its there its an immobilizer ecu which you do not want, if it is blank and just the metal ecu case there, its a non immobilizer that will work with swaps
http://wilbo666.pbworks.com/w/page/4...ngine%20Wiring
It is possible the maf setup can give us issues again, but for factory vvti control I am not sure how to avoid it just yet.
I am hoping the maf tune has evolved a bit more on vvti as even the 1jz vvti uses a maf setup (1jz vvti has no map sensor even cause its single turbo).
Unless someone learns how to control vvti individually, or going to a standalone, the best bet is probably the maf setup in conjunction with a piggyback like the aem fic which can use a map sensor and take over fueling etc..
its complicated but I figure worst case an aem fic or something similar would probably get it to work right. how bad can it be lol., there is no obd2 anyways with the vvti gte ecu.