SC300 12v Fuel Mod w/ Pictures - FAQ
04-08-14, 03:49 PM
#211
Dang Ali. You making me rethink this whole thing. Haha jk.
Well I'm not highly modified yet but I do plan on it eventually. But seeing as I already am doing most of the wiring to not have to do it again, I just wanted to do this so my future 2jzgte can have all the fuel needed, I wanted to get it done right. So now y I ure saying solder the old pump ecu back on, put the green wire that used to power the pump to trigger the relay, and then just wire the fuel pump like my old diagram. Battery to 30 amp fuse to pin 30 on relay to pin 87 then to fuel pump?
Well I'm not highly modified yet but I do plan on it eventually. But seeing as I already am doing most of the wiring to not have to do it again, I just wanted to do this so my future 2jzgte can have all the fuel needed, I wanted to get it done right. So now y I ure saying solder the old pump ecu back on, put the green wire that used to power the pump to trigger the relay, and then just wire the fuel pump like my old diagram. Battery to 30 amp fuse to pin 30 on relay to pin 87 then to fuel pump?
04-09-14, 07:45 AM
#212
Dang Ali. You making me rethink this whole thing. Haha jk.
Well I'm not highly modified yet but I do plan on it eventually. But seeing as I already am doing most of the wiring to not have to do it again, I just wanted to do this so my future 2jzgte can have all the fuel needed, I wanted to get it done right. So now y I ure saying solder the old pump ecu back on, put the green wire that used to power the pump to trigger the relay, and then just wire the fuel pump like my old diagram. Battery to 30 amp fuse to pin 30 on relay to pin 87 then to fuel pump?
Well I'm not highly modified yet but I do plan on it eventually. But seeing as I already am doing most of the wiring to not have to do it again, I just wanted to do this so my future 2jzgte can have all the fuel needed, I wanted to get it done right. So now y I ure saying solder the old pump ecu back on, put the green wire that used to power the pump to trigger the relay, and then just wire the fuel pump like my old diagram. Battery to 30 amp fuse to pin 30 on relay to pin 87 then to fuel pump?
Yes If you keep the stock fuel pump ecu in, and use the green wire going to the fuel pump to trigger the relay, you will get maximum fuel flow from your pump and you will retain all safety features!!!
The other thing to note is, people are always saying to do this when you go turbo or swap cause you need extra fuel blah blah blah. I don't buy it anymore. I had the mod done and then I undid it and noticed no lack of fuel at all in the lower power ranges. All it did for me was make the pump noisy at idle and had excess fuel returning through the rail. By the time you put your foot into it the pump has pretty much switched from 9V to 12v. If you also are using a gte ecu it may control the pump even better bu it basically sends the same signals to the fuel pump ecu, and I never hear really about supra owners doing it so I don't know why we would have to, and yes supras have a similar 9v/12v fuel pump ecu operation.
Sure if you wan't it to be 12v all the time go for it, keep the fuel ecu in and it will be safe. If its not broken no need to remove it I say, although if you had a wideband you may notice its just as unnecessary as seafoaming your motor oil.
04-09-14, 09:17 AM
#213
I heard that if you are using a Supra TT fuel pump that the pump will not turn on without the 12V mod...I did it to my car before....but I should change it back to how it was and see if my Supra TT pump still turns on with it going through Fuel Pump ECU...
04-09-14, 03:07 PM
#214
I think that is a supra TT pump specific issue and some say it works and some say it doesn't.
I would tell you but I have a walboro and it runs just fine off the stock fuel ecu. never had an issue with it.
I read that thread where Kurt chimed in and though it was mentioned he thought that the tt fuel pump drew too many amps for the stock n/a fuel ecu. it draws those 19 amps at the 12v setting and at the 9v it would draw much less. I think the real problem here is not a problem of the n/a fuel ecu being deisnged badly, but I think it happens when people go standalone and ones like the aem etc.. have to send a signal to the fuel pump ecu or it would not be plug and play, and by default the pulsewidth signal it sends to the fuel pump ecu is designed to run the fuel pump ecu @ 12V all the time, it never switches to 9v by default. I think this is what causes it to not work for half the people as no one mentions what ecu they use but I am pretty sure Kurt was on an aem at the time by the other comments he made.
The funny thing is if you are on a standalone, you do not need the fuel pump ecu at all, the standalone can safely run the pump with just a regular relay and cut off in an emergency still, you just use one of the grounded outputs on the ecu to turn the relay on and set the output on the standalone to the fuel pump operation mode or set the parameters up manually.
So the big question is is there actually any difference between the n/a and turbo fuel ecu, or are we just overheating the n/a one by making it run the beastly tt pump at 12v full time. Answer to that is I don't know for sure, but I would guess if you have a stock type ecu that will control the fuel ecu properly and keep it in 9v half of the time, you would be less likely to have an issue.
most people don't know that the aem v1 by default tells the fuel pump ecu to run full 12v, and its really not designed to do that but it can on a walboro, mine was like that for a year before I learnt about the issue because walboro's pull a little less amps at 12V which is within the limits of the stock ecu can handle for a given period of time. The times its in 9v is a break for the fuel ecu and your fuel system in general and is a good thing, at 12V all the time you just heat up extra fuel by shooting excess up and down the lines.
Worst case though you can see how you could just install a TT fuel ecu or run a relay off the output of the n/a fuel ecu.
Likely the TT fuel ecu has the same number of wires and could even have the same connector, but it wouldn't be hard to swap connectors anyways. Its funny I have never heard of anyone doing that, but If I had done the TT pump and it wasn't working even with the stock ecu that is likely what I would do instead of making it run 12v all the time with the relay.
maybe you can let us know how it goes when you undo it.. but as I understand it it works for some and for others it doesn't. If you are on the GE or GTE ecu it should work I would think, or my theory is bust =(
I would tell you but I have a walboro and it runs just fine off the stock fuel ecu. never had an issue with it.
I read that thread where Kurt chimed in and though it was mentioned he thought that the tt fuel pump drew too many amps for the stock n/a fuel ecu. it draws those 19 amps at the 12v setting and at the 9v it would draw much less. I think the real problem here is not a problem of the n/a fuel ecu being deisnged badly, but I think it happens when people go standalone and ones like the aem etc.. have to send a signal to the fuel pump ecu or it would not be plug and play, and by default the pulsewidth signal it sends to the fuel pump ecu is designed to run the fuel pump ecu @ 12V all the time, it never switches to 9v by default. I think this is what causes it to not work for half the people as no one mentions what ecu they use but I am pretty sure Kurt was on an aem at the time by the other comments he made.
The funny thing is if you are on a standalone, you do not need the fuel pump ecu at all, the standalone can safely run the pump with just a regular relay and cut off in an emergency still, you just use one of the grounded outputs on the ecu to turn the relay on and set the output on the standalone to the fuel pump operation mode or set the parameters up manually.
So the big question is is there actually any difference between the n/a and turbo fuel ecu, or are we just overheating the n/a one by making it run the beastly tt pump at 12v full time. Answer to that is I don't know for sure, but I would guess if you have a stock type ecu that will control the fuel ecu properly and keep it in 9v half of the time, you would be less likely to have an issue.
most people don't know that the aem v1 by default tells the fuel pump ecu to run full 12v, and its really not designed to do that but it can on a walboro, mine was like that for a year before I learnt about the issue because walboro's pull a little less amps at 12V which is within the limits of the stock ecu can handle for a given period of time. The times its in 9v is a break for the fuel ecu and your fuel system in general and is a good thing, at 12V all the time you just heat up extra fuel by shooting excess up and down the lines.
Worst case though you can see how you could just install a TT fuel ecu or run a relay off the output of the n/a fuel ecu.
Likely the TT fuel ecu has the same number of wires and could even have the same connector, but it wouldn't be hard to swap connectors anyways. Its funny I have never heard of anyone doing that, but If I had done the TT pump and it wasn't working even with the stock ecu that is likely what I would do instead of making it run 12v all the time with the relay.
maybe you can let us know how it goes when you undo it.. but as I understand it it works for some and for others it doesn't. If you are on the GE or GTE ecu it should work I would think, or my theory is bust =(
Last edited by Ali SC3; 04-09-14 at 03:13 PM.
04-09-14, 09:26 PM
#215
Ali, I was thinking of just PMing you about this but after reading your last couple of posts I'm posting here.
I just took delivery of a USDM TT fuel ECU as I plan to wire it up in stock configuration with the OEM USDM TT fuel pump. I still need the pump, hanger(s) and other bits before I try it but I'd be happy and appreciative to keep you informed of that side project when it comes time.
And I've wondered something, since I've been changing my car in stages: is it possible to install the US TT fuel pump and the TT fuel ECU (with EFI2 wiring?) but allow it to fuel my stock NA 2JZ-GE in the interim before I am ready to swap in my engine or convert my existing block? Forgive this if it's a no-brainer question. I would do this much closer to when I am ready, obviously.
I am also very interested in the safety features and longevity the TT fuel ECU supposedly provides over the NA fuel ECU. The shutoff feature in the case of (god forbid) an accident is very important to me, as I don't have a track car.
I just took delivery of a USDM TT fuel ECU as I plan to wire it up in stock configuration with the OEM USDM TT fuel pump. I still need the pump, hanger(s) and other bits before I try it but I'd be happy and appreciative to keep you informed of that side project when it comes time.
And I've wondered something, since I've been changing my car in stages: is it possible to install the US TT fuel pump and the TT fuel ECU (with EFI2 wiring?) but allow it to fuel my stock NA 2JZ-GE in the interim before I am ready to swap in my engine or convert my existing block? Forgive this if it's a no-brainer question. I would do this much closer to when I am ready, obviously.
I am also very interested in the safety features and longevity the TT fuel ECU supposedly provides over the NA fuel ECU. The shutoff feature in the case of (god forbid) an accident is very important to me, as I don't have a track car.
04-09-14, 11:07 PM
#216
I think that is a supra TT pump specific issue and some say it works and some say it doesn't.
I would tell you but I have a walboro and it runs just fine off the stock fuel ecu. never had an issue with it.
I read that thread where Kurt chimed in and though it was mentioned he thought that the tt fuel pump drew too many amps for the stock n/a fuel ecu. it draws those 19 amps at the 12v setting and at the 9v it would draw much less. I think the real problem here is not a problem of the n/a fuel ecu being deisnged badly, but I think it happens when people go standalone and ones like the aem etc.. have to send a signal to the fuel pump ecu or it would not be plug and play, and by default the pulsewidth signal it sends to the fuel pump ecu is designed to run the fuel pump ecu @ 12V all the time, it never switches to 9v by default. I think this is what causes it to not work for half the people as no one mentions what ecu they use but I am pretty sure Kurt was on an aem at the time by the other comments he made.
The funny thing is if you are on a standalone, you do not need the fuel pump ecu at all, the standalone can safely run the pump with just a regular relay and cut off in an emergency still, you just use one of the grounded outputs on the ecu to turn the relay on and set the output on the standalone to the fuel pump operation mode or set the parameters up manually.
So the big question is is there actually any difference between the n/a and turbo fuel ecu, or are we just overheating the n/a one by making it run the beastly tt pump at 12v full time. Answer to that is I don't know for sure, but I would guess if you have a stock type ecu that will control the fuel ecu properly and keep it in 9v half of the time, you would be less likely to have an issue.
most people don't know that the aem v1 by default tells the fuel pump ecu to run full 12v, and its really not designed to do that but it can on a walboro, mine was like that for a year before I learnt about the issue because walboro's pull a little less amps at 12V which is within the limits of the stock ecu can handle for a given period of time. The times its in 9v is a break for the fuel ecu and your fuel system in general and is a good thing, at 12V all the time you just heat up extra fuel by shooting excess up and down the lines.
Worst case though you can see how you could just install a TT fuel ecu or run a relay off the output of the n/a fuel ecu.
Likely the TT fuel ecu has the same number of wires and could even have the same connector, but it wouldn't be hard to swap connectors anyways. Its funny I have never heard of anyone doing that, but If I had done the TT pump and it wasn't working even with the stock ecu that is likely what I would do instead of making it run 12v all the time with the relay.
maybe you can let us know how it goes when you undo it.. but as I understand it it works for some and for others it doesn't. If you are on the GE or GTE ecu it should work I would think, or my theory is bust =(
I would tell you but I have a walboro and it runs just fine off the stock fuel ecu. never had an issue with it.
I read that thread where Kurt chimed in and though it was mentioned he thought that the tt fuel pump drew too many amps for the stock n/a fuel ecu. it draws those 19 amps at the 12v setting and at the 9v it would draw much less. I think the real problem here is not a problem of the n/a fuel ecu being deisnged badly, but I think it happens when people go standalone and ones like the aem etc.. have to send a signal to the fuel pump ecu or it would not be plug and play, and by default the pulsewidth signal it sends to the fuel pump ecu is designed to run the fuel pump ecu @ 12V all the time, it never switches to 9v by default. I think this is what causes it to not work for half the people as no one mentions what ecu they use but I am pretty sure Kurt was on an aem at the time by the other comments he made.
The funny thing is if you are on a standalone, you do not need the fuel pump ecu at all, the standalone can safely run the pump with just a regular relay and cut off in an emergency still, you just use one of the grounded outputs on the ecu to turn the relay on and set the output on the standalone to the fuel pump operation mode or set the parameters up manually.
So the big question is is there actually any difference between the n/a and turbo fuel ecu, or are we just overheating the n/a one by making it run the beastly tt pump at 12v full time. Answer to that is I don't know for sure, but I would guess if you have a stock type ecu that will control the fuel ecu properly and keep it in 9v half of the time, you would be less likely to have an issue.
most people don't know that the aem v1 by default tells the fuel pump ecu to run full 12v, and its really not designed to do that but it can on a walboro, mine was like that for a year before I learnt about the issue because walboro's pull a little less amps at 12V which is within the limits of the stock ecu can handle for a given period of time. The times its in 9v is a break for the fuel ecu and your fuel system in general and is a good thing, at 12V all the time you just heat up extra fuel by shooting excess up and down the lines.
Worst case though you can see how you could just install a TT fuel ecu or run a relay off the output of the n/a fuel ecu.
Likely the TT fuel ecu has the same number of wires and could even have the same connector, but it wouldn't be hard to swap connectors anyways. Its funny I have never heard of anyone doing that, but If I had done the TT pump and it wasn't working even with the stock ecu that is likely what I would do instead of making it run 12v all the time with the relay.
maybe you can let us know how it goes when you undo it.. but as I understand it it works for some and for others it doesn't. If you are on the GE or GTE ecu it should work I would think, or my theory is bust =(
Anyways, after I read your first post telling me to reinstall it, I was just gonna end up buying a new one and wait around for that. But now I just read this post, ^^^, and that says that standalone ecu's can do the same thing, (shut the fuel pump off in case of an accident,) well I don't have a standalone yet but I plan on getting one after I go gte. So for now I'm just gonna leave it this way until then. Drive my car the way it is until I get my standalone.
04-10-14, 09:55 AM
#217
Ali, I was thinking of just PMing you about this but after reading your last couple of posts I'm posting here.
I just took delivery of a USDM TT fuel ECU as I plan to wire it up in stock configuration with the OEM USDM TT fuel pump. I still need the pump, hanger(s) and other bits before I try it but I'd be happy and appreciative to keep you informed of that side project when it comes time.
And I've wondered something, since I've been changing my car in stages: is it possible to install the US TT fuel pump and the TT fuel ECU (with EFI2 wiring?) but allow it to fuel my stock NA 2JZ-GE in the interim before I am ready to swap in my engine or convert my existing block? Forgive this if it's a no-brainer question. I would do this much closer to when I am ready, obviously.
I am also very interested in the safety features and longevity the TT fuel ECU supposedly provides over the NA fuel ECU. The shutoff feature in the case of (god forbid) an accident is very important to me, as I don't have a track car.
I just took delivery of a USDM TT fuel ECU as I plan to wire it up in stock configuration with the OEM USDM TT fuel pump. I still need the pump, hanger(s) and other bits before I try it but I'd be happy and appreciative to keep you informed of that side project when it comes time.
And I've wondered something, since I've been changing my car in stages: is it possible to install the US TT fuel pump and the TT fuel ECU (with EFI2 wiring?) but allow it to fuel my stock NA 2JZ-GE in the interim before I am ready to swap in my engine or convert my existing block? Forgive this if it's a no-brainer question. I would do this much closer to when I am ready, obviously.
I am also very interested in the safety features and longevity the TT fuel ECU supposedly provides over the NA fuel ECU. The shutoff feature in the case of (god forbid) an accident is very important to me, as I don't have a track car.
You can absolutely do it before hand, there is no issue with having extra fuel going through the system that you would notice. It does cause the fuel to heat up a little more but that is only an issue with turbocharged cars really or cars pushing the envelope or performance.
I think you are doing the right thing by removing the doubt when using the TT pump to use the TT fuel ecu until we know for sure that the n/a doesn't work, but if you can get your hands on one and sounds like you already have one, I can;t think of a reason I wouldn't do it that way since you are using a GTE ecu. Toyota ecu's I say keep the fuel ecu, even if yours craps out replace it with another one of now I would just say try and get a supra TT one.
Sometimes in an accident you get incapacitated, and you cannot simply reach for the key and turn it off, and the way you choose to wire up your fuel pump can make all the difference.
I sort of wish no one told anyone else the quick way to bypass it but it has its uses I guess.
Do not hold your breath while you try to read that. Lol. That is a mouthful. Anyways, I was so close to reinstalling/soldering my stock ge fuel pump ecu back in, all because of what you said earlier, but sadly I completely through it away. I figured I didn't need it anymore and the chances of me selling it are highly unlikely.
Anyways, after I read your first post telling me to reinstall it, I was just gonna end up buying a new one and wait around for that. But now I just read this post, ^^^, and that says that standalone ecu's can do the same thing, (shut the fuel pump off in case of an accident,) well I don't have a standalone yet but I plan on getting one after I go gte. So for now I'm just gonna leave it this way until then. Drive my car the way it is until I get my standalone.
Anyways, after I read your first post telling me to reinstall it, I was just gonna end up buying a new one and wait around for that. But now I just read this post, ^^^, and that says that standalone ecu's can do the same thing, (shut the fuel pump off in case of an accident,) well I don't have a standalone yet but I plan on getting one after I go gte. So for now I'm just gonna leave it this way until then. Drive my car the way it is until I get my standalone.
Yeah all the standalone have a fuel pump control function that you typically wire up with a relay. The aem will cut it off below a certain rpm as well as a bunch of other conditions you can just enter yourself. The idea is when the motor cuts out you want the fuel to cut out, always. There are also some things in case of a rollover but those are more physically on the tank itself but you don;t want the pump going still.
04-10-14, 01:37 PM
#218
Kahn I like the way you approach these mods. I think you can use the stock hanger its basically the same thing, just strap the TT pump to it, the TT pump will have a larger diameter but otherwise is mostly the same.
You can absolutely do it before hand, there is no issue with having extra fuel going through the system that you would notice. It does cause the fuel to heat up a little more but that is only an issue with turbocharged cars really or cars pushing the envelope or performance.
You can absolutely do it before hand, there is no issue with having extra fuel going through the system that you would notice. It does cause the fuel to heat up a little more but that is only an issue with turbocharged cars really or cars pushing the envelope or performance.
I am attempting to source a stock fuel hanger at the moment. I do in fact have a spare TT fuel ECU. I can double-check the P/N with the guys at Carson but I am not concerned.So with my bone-stock 2JZ-GE engine and 330cc injector fuel system, the TT ECU & TT USDM Denso pump should be fine? I wonder... is a potential drawback going to be decreased fuel economy from the extra fuel pressure? Given that without turbocharging (yet) there is no need for extra fuel, really. The heated fuel seems ok I guess but wouldn't that also affect cylinder temperatures and possibly get closer to knock without the benefit of cooled air from an intercooler? ALL GUESSES but it occurred to me that it might also factor in. I ask because I wonder if it's messing with the basic principles of tuning a bit too much without accounting for elevated fuel temperature.
FYI to anyone reading this, if you aren't "staging" your modifications as I am with a daily driven car this is probably meaningless with a car that is not seeing road duty during a full swap or engine build.
I think you are doing the right thing by removing the doubt when using the TT pump to use the TT fuel ecu until we know for sure that the n/a doesn't work, but if you can get your hands on one and sounds like you already have one, I can;t think of a reason I wouldn't do it that way since you are using a GTE ecu. Toyota ecu's I say keep the fuel ecu, even if yours craps out replace it with another one of now I would just say try and get a supra TT one.
I do have an OBD1 USDM GTE ECU waiting to be used BUT I was actually asking this question with my NA ECU and the distributor-ignition system in mind. I do wonder if the TT ECU would accept it regardless of whether or not the EFI2 wire actually connects to anything yet.
As we've discussed, Ali, in my case I'm not doing any distributor delete. I'm doing a full top end stock conversion so in terms of switching to the GTE ECU and installing the custom wiring harness, all of that pretty much will happen in one go.
Sometimes in an accident you get incapacitated, and you cannot simply reach for the key and turn it off, and the way you choose to wire up your fuel pump can make all the difference.
I sort of wish no one told anyone else the quick way to bypass it but it has its uses I guess.
I sort of wish no one told anyone else the quick way to bypass it but it has its uses I guess.
I wholeheartedly agree with you on this!
Last edited by KahnBB6; 04-10-14 at 01:43 PM.
04-10-14, 03:15 PM
#219
Thanks, Ali! I am attempting to source a stock fuel hanger at the moment. I do in fact have a spare TT fuel ECU. I can double-check the P/N with the guys at Carson but I am not concerned.
So with my bone-stock 2JZ-GE engine and 330cc injector fuel system, the TT ECU & TT USDM Denso pump should be fine? I wonder... is a potential drawback going to be decreased fuel economy from the extra fuel pressure? Given that without turbocharging (yet) there is no need for extra fuel, really. The heated fuel seems ok I guess but wouldn't that also affect cylinder temperatures and possibly get closer to knock without the benefit of cooled air from an intercooler? ALL GUESSES but it occurred to me that it might also factor in. I ask because I wonder if it's messing with the basic principles of tuning a bit too much without accounting for elevated fuel temperature.
FYI to anyone reading this, if you aren't "staging" your modifications as I am with a daily driven car this is probably meaningless with a car that is not seeing road duty during a full swap or engine build.
Yes, this was my thinking. Additionally, since I'm pretty sure at this point I'm going to go no higher than 15psi w/91 octane pump gas which is far from pushing the actual drivetrain I might as well wire things up to take advantage of the longevity feature of the 9V mode when not under boost.
I do have an OBD1 USDM GTE ECU waiting to be used BUT I was actually asking this question with my NA ECU and the distributor-ignition system in mind. I do wonder if the TT ECU would accept it regardless of whether or not the EFI2 wire actually connects to anything yet.
As we've discussed, Ali, in my case I'm not doing any distributor delete. I'm doing a full top end stock conversion so in terms of switching to the GTE ECU and installing the custom wiring harness, all of that pretty much will happen in one go.
Yes, and this is absolutely crucial on any stock or swapped street vehicle in my opinion. Even more so on a dedicated track car given the higher risks involved.
I wholeheartedly agree with you on this!
I am attempting to source a stock fuel hanger at the moment. I do in fact have a spare TT fuel ECU. I can double-check the P/N with the guys at Carson but I am not concerned.So with my bone-stock 2JZ-GE engine and 330cc injector fuel system, the TT ECU & TT USDM Denso pump should be fine? I wonder... is a potential drawback going to be decreased fuel economy from the extra fuel pressure? Given that without turbocharging (yet) there is no need for extra fuel, really. The heated fuel seems ok I guess but wouldn't that also affect cylinder temperatures and possibly get closer to knock without the benefit of cooled air from an intercooler? ALL GUESSES but it occurred to me that it might also factor in. I ask because I wonder if it's messing with the basic principles of tuning a bit too much without accounting for elevated fuel temperature.
FYI to anyone reading this, if you aren't "staging" your modifications as I am with a daily driven car this is probably meaningless with a car that is not seeing road duty during a full swap or engine build.
Yes, this was my thinking. Additionally, since I'm pretty sure at this point I'm going to go no higher than 15psi w/91 octane pump gas which is far from pushing the actual drivetrain I might as well wire things up to take advantage of the longevity feature of the 9V mode when not under boost.
I do have an OBD1 USDM GTE ECU waiting to be used BUT I was actually asking this question with my NA ECU and the distributor-ignition system in mind. I do wonder if the TT ECU would accept it regardless of whether or not the EFI2 wire actually connects to anything yet.
As we've discussed, Ali, in my case I'm not doing any distributor delete. I'm doing a full top end stock conversion so in terms of switching to the GTE ECU and installing the custom wiring harness, all of that pretty much will happen in one go.
Yes, and this is absolutely crucial on any stock or swapped street vehicle in my opinion. Even more so on a dedicated track car given the higher risks involved.
I wholeheartedly agree with you on this!
Yeah with bone stock system it will be fine. no MPG's will be affected. The fuel pressure regulator at the end of the rail will release the extra pressure via the return line, and since the feed and return line are physically similar in size you won't get into a situation where your base pressure will exceed what the regulator will return, unless you upgraded your fuel feed line.
What happens is that more fuel is redirected by the regulator to the return, and this sending of extra fuel there and back add's heat to the fuel. The 9v operation though will prevent this from happening in excess really until its appropriate to be at 12v and then for that short bit of time returning some extra fuel wont really hurt much at all, some fuel is being returned anyways.
Don't worry about when you do it, it should operate fine on the n/a and gte ecu, right now my gte ecu is controlling my stock n/a fuel ecu with a walboro pump. Go ahead and do the tt pump and the tt fuel ecu at the same time though whenever you do it.
The important thing is that you have the capacity for the power you are going to run, extra will be returned by the regulator and at 9v/12v operation you wont have any issues. even if you run it at 12v at idle it would be fine but they don't do it that way from factory because why make the regulator work so hard.
04-10-14, 05:03 PM
#220
Yes, I can I'll dig it out in a bit and post a couple of pictures.
I love it. What a great system. I'll probably still wait on it until I have the new engine on the stand at least but it's great to know I can tackle it independently of the engine swap so as to tackle the EFI2 wire ahead of time.
Yeah, I realize it's rare to see a fuel pump that operates this way but it's kind of a neat design idea. I imagine that with the extra flow of the TT pump it might not go into 12V mode nearly as often as the stock NA pump would on the stock GE fuel system. Although isn't the older 1JZ supposed to have 380cc injectors stock? If so it's not too much difference from 330cc.
I'll dig it out in a bit and post a couple of pictures.Yeah with bone stock system it will be fine. no MPG's will be affected. The fuel pressure regulator at the end of the rail will release the extra pressure via the return line, and since the feed and return line are physically similar in size you won't get into a situation where your base pressure will exceed what the regulator will return, unless you upgraded your fuel feed line.
What happens is that more fuel is redirected by the regulator to the return, and this sending of extra fuel there and back add's heat to the fuel. The 9v operation though will prevent this from happening in excess really until its appropriate to be at 12v and then for that short bit of time returning some extra fuel wont really hurt much at all, some fuel is being returned anyways.
What happens is that more fuel is redirected by the regulator to the return, and this sending of extra fuel there and back add's heat to the fuel. The 9v operation though will prevent this from happening in excess really until its appropriate to be at 12v and then for that short bit of time returning some extra fuel wont really hurt much at all, some fuel is being returned anyways.
Don't worry about when you do it, it should operate fine on the n/a and gte ecu, right now my gte ecu is controlling my stock n/a fuel ecu with a walboro pump. Go ahead and do the tt pump and the tt fuel ecu at the same time though whenever you do it.
The important thing is that you have the capacity for the power you are going to run, extra will be returned by the regulator and at 9v/12v operation you wont have any issues. even if you run it at 12v at idle it would be fine but they don't do it that way from factory because why make the regulator work so hard.
The important thing is that you have the capacity for the power you are going to run, extra will be returned by the regulator and at 9v/12v operation you wont have any issues. even if you run it at 12v at idle it would be fine but they don't do it that way from factory because why make the regulator work so hard.
04-13-14, 12:26 AM
#223
According to these threads the USDM TT Fuel ECU may not plug right into the SC body harness:
http://www.supraforums.com/forum/sho...ht=tt+fuel+ecu
http://www.supraforums.com/forum/sho...+fuel+ecu+swap
I have no way to verify this right now. I'm inclined to try to buy a new matching male connector or a used one with wire leads still connected.
What do you think, Ali?
And Estomax-- love to hear any updates on your car's progress!
http://www.supraforums.com/forum/sho...ht=tt+fuel+ecu
http://www.supraforums.com/forum/sho...+fuel+ecu+swap
I have no way to verify this right now. I'm inclined to try to buy a new matching male connector or a used one with wire leads still connected.
What do you think, Ali?
And Estomax-- love to hear any updates on your car's progress!
Last edited by KahnBB6; 04-13-14 at 12:36 AM.
04-14-14, 12:48 PM
#224
Further info:
I just spoke to Curt Aigner at Elmhurst Toyota thinking I had an easy out to locate the connector. Here's the good news: I have a part number!
90980-11362 connector for TT fuel ECU
And the electrical wire/leads that go to it are available (for about $50 or so total)
The bad news is that, as you might have guessed, you cannot buy that connector individually. It is only available on the body harness that goes to the left rear trunk location on Supra MKIV TT's. And that harness has long since been discontinued.
Curt did tell me that the gauge of wiring in either the Supra NA and TT at the fuel pump ECU location are the same. Interesting.
There is a way to do this but it involves finding that connector. Additionally, Curt directed me to Stu Hagen's (of Hybrid GT28 USDM twin turbo fame) website where there are original Toyota wiring schematics that should depict the pinouts for the TT Fuel ECU:
http://97supraturbo.com/Tech.html
For now it seems this will be at an impasse for me until I know more.
All this post relates to is just trying to get this ECU hooked up in the first place let alone tested. And as I mentioned above, apparently Supra MKIV NA owners also have this issue of the TT fuel ECU having a different connector than the NA.
These issues might give some credence as to why this 12V fuel mod has such popularity.
I just spoke to Curt Aigner at Elmhurst Toyota thinking I had an easy out to locate the connector. Here's the good news: I have a part number!
90980-11362 connector for TT fuel ECU
And the electrical wire/leads that go to it are available (for about $50 or so total)
The bad news is that, as you might have guessed, you cannot buy that connector individually. It is only available on the body harness that goes to the left rear trunk location on Supra MKIV TT's. And that harness has long since been discontinued.
Curt did tell me that the gauge of wiring in either the Supra NA and TT at the fuel pump ECU location are the same. Interesting.
There is a way to do this but it involves finding that connector. Additionally, Curt directed me to Stu Hagen's (of Hybrid GT28 USDM twin turbo fame) website where there are original Toyota wiring schematics that should depict the pinouts for the TT Fuel ECU:
http://97supraturbo.com/Tech.html
For now it seems this will be at an impasse for me until I know more.
All this post relates to is just trying to get this ECU hooked up in the first place let alone tested. And as I mentioned above, apparently Supra MKIV NA owners also have this issue of the TT fuel ECU having a different connector than the NA.
These issues might give some credence as to why this 12V fuel mod has such popularity.
