tt head on a 99 gs300
#16
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Piggy back which Ecu?
What I'm trying to get at is that the TT ecu doesn't plug in so if you want it to control the motor you will need to completely alter the harness from the stock GS ecu to go the the TT ecu. BUT, the TT ecu won't drive your gauges etc.... so unless you decide you want to drive around without gauges and a properly functioning transmission etc... then you need to ALSO have the stock GS ECU wired in as well so that your gauges, transmission etc...will work correctly.
Again, please remember that Jeff is using a $1000 plus engine management system to run his setup instead of adding the TT ecu. If you really want to stick to a stock setup you would have better luck finding a Vvti TT head assembly from a late generation Aristo (like Jeff has) and then using the Aristo ecu and harness which will actually mount in the stock location, drive your gauges, have plugs already there for all the sensors including the turbo stuff and also have proper timing/fuel control for using the TT head. At that point you could also install a TT transmission (which is much stronger than the stock GS trans and will last much longer, not to mention they are only about $250 shipped), throw an AFC on there and you will have a car that drives like stock, makes big power and has a nice strong transmission as well.
What I'm trying to get at is that the TT ecu doesn't plug in so if you want it to control the motor you will need to completely alter the harness from the stock GS ecu to go the the TT ecu. BUT, the TT ecu won't drive your gauges etc.... so unless you decide you want to drive around without gauges and a properly functioning transmission etc... then you need to ALSO have the stock GS ECU wired in as well so that your gauges, transmission etc...will work correctly.
Again, please remember that Jeff is using a $1000 plus engine management system to run his setup instead of adding the TT ecu. If you really want to stick to a stock setup you would have better luck finding a Vvti TT head assembly from a late generation Aristo (like Jeff has) and then using the Aristo ecu and harness which will actually mount in the stock location, drive your gauges, have plugs already there for all the sensors including the turbo stuff and also have proper timing/fuel control for using the TT head. At that point you could also install a TT transmission (which is much stronger than the stock GS trans and will last much longer, not to mention they are only about $250 shipped), throw an AFC on there and you will have a car that drives like stock, makes big power and has a nice strong transmission as well.
Last edited by macd7919; 03-27-10 at 01:02 AM.
#17
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The SAFC2 will get you nowhere with these cars if you're looking to increase power reliably. At the VERY minimum, at least get a AEM FIC or a Emanage Ultimate. Best case scenario is to go with a standalone, but I realize this is not a step many people are willing to make.
As for the sensors and electronic valves, all of them will still be in use. The only ones that you will take off are for the VSV for the twin turbo stuff if you decide to go single.
Please do more research into what you're really getting yourself into before you start. Not trying to discourage you or anything, just keeping you in reality check. It seems like you have pretty good resources to get everything ironed out, but please don't just think it's an easy drop in and drive away kind of deal.
There are 2 ways to go about the swap.
1. Stock GS ecu + piggyback or standalone. This is the route I went with. It involves the least amount of rewiring(this is just saying relatively...there's still a lot of rewiring to do). This is the best option you want to do if you are planning to go with a standalone.
2. Remove stock GS ecu and rebuild the wiring harness for an Aristo TT ecu to replace the stock GS ecu. This is a good option if you want to have very good OEM reliability. You can't beat the stock Toyota ECU when it comes to reliability, consistency, and fuel economy. This way requires a LOT more wiring, but in the end it is better if you are staying near stock GTE power(or slightly elevated) with a piggyback and do not plan to add a standalone on top.
As for the sensors and electronic valves, all of them will still be in use. The only ones that you will take off are for the VSV for the twin turbo stuff if you decide to go single.
Please do more research into what you're really getting yourself into before you start. Not trying to discourage you or anything, just keeping you in reality check. It seems like you have pretty good resources to get everything ironed out, but please don't just think it's an easy drop in and drive away kind of deal.
There are 2 ways to go about the swap.
1. Stock GS ecu + piggyback or standalone. This is the route I went with. It involves the least amount of rewiring(this is just saying relatively...there's still a lot of rewiring to do). This is the best option you want to do if you are planning to go with a standalone.
2. Remove stock GS ecu and rebuild the wiring harness for an Aristo TT ecu to replace the stock GS ecu. This is a good option if you want to have very good OEM reliability. You can't beat the stock Toyota ECU when it comes to reliability, consistency, and fuel economy. This way requires a LOT more wiring, but in the end it is better if you are staying near stock GTE power(or slightly elevated) with a piggyback and do not plan to add a standalone on top.
Last edited by JeffTsai; 03-27-10 at 12:57 AM.
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