Na-t fuel injectors + pump questions

[supra brit]

Sorry guys, I'm still new to the Supra na-t (I can tell you anything about a turbo 240 though haha)...anyways.

Just a few questions about fuel system upgrades...

I've read about people using 440cc's out of a mkiii...can I just use 2jzgte injectors (I work @ Napa and get a *good* discount), a TT fuel pump, TT regulator, and FP ECU? What else would I need to change? What size are TT injectors?

Any info would be great, thanks guys. :biggrin:

[LexusFTW]

the gte injectors are side feed and wont work with the NA fuel rail. the TT fuel pump will work and is recommended. Get an aftermarket fpr, look at Mark's fpr. FP ECU? Never heard of it. Stock gte injectors are 550cc low impedence.

How much power do you want to make?

[supra brit]

I thought the TT fuel pumps had a different computer (not main engine computer, but the actual fuel pump computer)

At the moment, I would be happy with around 300-325hp. So 7mgte injectors will do? What size are the na's?

[LexusFTW]

O! Fuel Pump ECU. No, there's no need to get the TT Fuel pump ECU. I would do the 12v fuel pump mod and ditch the fuel pump ECU. For that power, 7m injectors will work perfect! NA's are 330 and high impedence. The 7m injectors are low impedence and will require a resistor pack to make them work. You can either get the 7m resistor pack or the mkiv TT.

[craaaazzy]

i say get the largest injectors u can. when i initially bought my kit, i had already upgraded to the 525's but even that wasn't enough and had to upgrade again. difference in price for injectors isn't that much. this is of course, getting brand new injectors, not used ones.

and yes to tt pump. i recommend the denso over the walbro's.

[supra brit]

Thanks guys...any other cars with injectors that would bea good upgrade? Eventually I will get something aftermarket, but for now, something from another car will probably do...

[LexusFTW]

Go with MKIII. They're cheap and abundant.

[craaaazzy]

the rx7 has 550 that are supposed to be plug and play as well. what's your budget for the injectors? and what r u using to control them?

[DrNick]

When do the NA pumps start to struggle? I cant find flow specs for them.

[supra brit]

I'm going to get them brand new @ Napa, haven;t priced them out yet but my discount is 10% over cost, so they shouldn't be too much.

[TurboSpoolinInside]

For that little of power, can't you just get by with the stock injectors, run low boost, get a TT pump or cheap walbro and call it good enough? I was thinking about actually seeing how far I could go w/ stock fuel (minus buying a pump) so I could actually mod once/go big at the same time (but in the mean time, stay small and use as many stock parts as possible) - (stock auto, stock fuel, stock ecu, stock compression) I was actually gonna ask something here, but I'll start a new thread.

[vivdownunder]

Can someone confirm if I can use the 1JZ 380cc injectors on a JDM 2JZGE?
I only plan to run 7 psi out of my na/t and my sock 315cc injectors are only good for 4 psi. I have installed fuel pump, rr FPR and safc. The a/f is good up to 4 psi and anything more it leans out. I am trying to find the easiest / plug and play injector upgrade for the JDM 2JZ GE
cheers
Viv

[bahamasupra]

I just installed 510 injectors that came from 3rd gen evo. with t-67 safc II

[Tim9]

For that little of power, can't you just get by with the stock injectors, run low boost, get a TT pump or cheap walbro and call it good enough? I was thinking about actually seeing how far I could go w/ stock fuel (minus buying a pump) so I could actually mod once/go big at the same time (but in the mean time, stay small and use as many stock parts as possible) - (stock auto, stock fuel, stock ecu, stock compression) I was actually gonna ask something here, but I'll start a new thread.

I have a kit from Powerhouse Racing that used the standard injectors, Walbro, Vortech Rising Rate Fuel Pressure Regulator that was supposed to be good for 320 RWHP, but I did not get that far with the boost as my JDM Supra had the timing spike that would not let me run more than 3PSI without detonating. However this used the standard injectors and should be OK to get that RWHP.

Tim

[DrNick]

Really , just 3psi? What fuel were you running?

Lots of people here seem to have managed to run more boost than that without touching the timing. I wonder if the JDM has different timing curve?

[suprachic83]

do it cheap, do it twice. do it right and you will save a lot in the long run. This is just from my personal experience. You never want to take shortcuts with the fuel aspect of forced induction. Could cost you a motor. Happened to me with nitrous and a turbo before.

[Mr Ree NZ]

Really , just 3psi? What fuel were you running?

Lots of people here seem to have managed to run more boost than that without touching the timing. I wonder if the JDM has different timing curve?

Hi DrNick:)

WHat sort of ecu does your car have? Mine is a jdm and I have read lots about the timing spike and people having problems over 3 or 4 psi. Seems like some people are affected by it and some arent?

Cheers

Mr Ree

[DrNick]

Hi DrNick:)

WHat sort of ecu does your car have? Mine is a jdm and I have read lots about the timing spike and people having problems over 3 or 4 psi. Seems like some people are affected by it and some arent?

Cheers

Mr Ree

Same , JDM GE ECU. You can feel the timing spike at 4.5K which coincides with the ACIS system kicking in. Although this was present on the USDM Supras as well so I would expect the timing curve to be exactly the same. It is a bit strange that some people have issues at such low psi.

It would be nice to see a data log of the timing. I cant datalog mine since it has the single signal from the distributor. But I'm guessing anyone who has got rid of the dizzy should be able to data log the ignition events from the cam angle sensors and answer the question once and for all.

[Mr Ree NZ]

Same , JDM GE ECU. You can feel the timing spike at 4.5K which coincides with the ACIS system kicking in. Although this was present on the USDM Supras as well so I would expect the timing curve to be exactly the same. It is a bit strange that some people have issues at such low psi.

It would be nice to see a data log of the timing. I cant datalog mine since it has the single signal from the distributor. But I'm guessing anyone who has got rid of the dizzy should be able to data log the ignition events from the cam angle sensors and answer the question once and for all.

Do you know how many degrees the timing changes at that point? Im sure it would be possible to smooth out the spike with the emanage ultimate if it would help make things safer. Also with the ACIS valve disabled do you think that would help at all or would the spike be preprogrammed into the factory ecu?

I want to do alot more reading about timing and na-t conversions so I can always err on the side of caution

Cheers

Mr Ree

[DrNick]

I have no idea how many degrees it advances because I can't datalog the ignition events with my setup. As far as I know the timing spike just coincides with the acis opening, it is not triggered by the acis. So disabling it will not make any difference. If the amount of advance was known then you're right it would be quite easy to subtract that many degrees from the stock ignition map at 4500+ rpm using the emu.
We could always do it by trial and error, just accelerate smoothly and keep taking off 1 degree at a time until the power feels completely linear. Although it would probably be a good idea to disable the acis first so that it doesnt confuse matters.

[Mr Ree NZ]

I have no idea how many degrees it advances because I can't datalog the ignition events with my setup. As far as I know the timing spike just coincides with the acis opening, it is not triggered by the acis. So disabling it will not make any difference. If the amount of advance was known then you're right it would be quite easy to subtract that many degrees from the stock ignition map at 4500+ rpm using the emu.
We could always do it by trial and error, just accelerate smoothly and keep taking off 1 degree at a time until the power feels completely linear. Although it would probably be a good idea to disable the acis first so that it doesnt confuse matters.

Indeed, that sounds like the plan.

once I get my ultimate installed and disable the asics valve I will get my friend with a scope to have a look and I will let you know what we find. Once we work out the timing change im sure we can, as you have said already alter the timing to keep it linear :)

Cheers

Mr Ree

[DrNick]

If you can do that it would be fantastic. I had another idea that it may be possible to use the NE and G signals inside the distributor to get values for crank and cam positions and feed these into the inputs on the emanage to monitor timing that way. It would be a bit of stuffing around though and I have a lot of other things to do before I would get time for an experiment like that.

BTW a hint for you when you install the emanage. The manual says to jumper JP13 if using a temperature sensor (such as intake water temp). I did this and the car overfuelled badly and was idling at 2.5K. I was getting correct readings in the datalog for water temp so I assumed this was ok, but today I pulled the jumper off and the idle and mixture returned to normal again. So ignore that bit of the manual. Leave all the jumpers in the stock position.
Since you have the following options for the 2 inputs

Knock1/Intake Water Temp
Knock2/Intake Air Temp

I suggest that you use Intake water and Knock2 . I haven't even got one knock sensor to work yet so I think that water temp is more important to monitor than having two knock sensors.

[Mr Ree NZ]

If you can do that it would be fantastic. I had another idea that it may be possible to use the NE and G signals inside the distributor to get values for crank and cam positions and feed these into the inputs on the emanage to monitor timing that way. It would be a bit of stuffing around though and I have a lot of other things to do before I would get time for an experiment like that.

BTW a hint for you when you install the emanage. The manual says to jumper JP13 if using a temperature sensor (such as intake water temp). I did this and the car overfuelled badly and was idling at 2.5K. I was getting correct readings in the datalog for water temp so I assumed this was ok, but today I pulled the jumper off and the idle and mixture returned to normal again. So ignore that bit of the manual. Leave all the jumpers in the stock position.
Since you have the following options for the 2 inputs

Knock1/Intake Water Temp
Knock2/Intake Air Temp

I suggest that you use Intake water and Knock2 . I haven't even got one knock sensor to work yet so I think that water temp is more important to monitor than having two knock sensors.

Thanks for the info mate, my friend wired in the computer last weekend so I will print out your post so he can read ity and see if he has to change anything.

Cheers

Mr Ree

[DrNick]

Thanks for the info mate, my friend wired in the computer last weekend so I will print out your post so he can read ity and see if he has to change anything.

Cheers

Mr Ree

Are you running NA with stock 330cc injectors? Try trimming some fuel to get to 13.5 AFR and see how smooth the car goes :)

I had some maps but the stupid a/f target map kept overwriting itself every time i plugged the laptop in, I'm a bit distracted with my new gearbox too but I'll save a map for you if you are using that setup.

[bahamasupra]

I have evo3 injectors in my supra. they are 510cc

[LexusFTW]

I have evo3 injectors in my supra. they are 510cc

Thanks for the info!

Can you tell us more about your setup? Stock GE fuel rail? high or low impedence?

[Mr Ree NZ]

Are you running NA with stock 330cc injectors? Try trimming some fuel to get to 13.5 AFR and see how smooth the car goes :)

I had some maps but the stupid a/f target map kept overwriting itself every time i plugged the laptop in, I'm a bit distracted with my new gearbox too but I'll save a map for you if you are using that setup.

Hi DrNick :)

I have bought some 440cc injectors from the 7mgte, I got a formula for how many% to remove for the start up tune so the plugs dont get wet. Any info you have is appreciated though.

I would be distracted with my gearbox too if I was you ;)

FYI, I put the head back on my car today, all pipework and turbo housing has been ceramic coated, all electrics are wired in, intercooler is mounted and pipework is all cut and fitted. Just have to weld an inch more length onto the mid pipe and weld the WB02 sensor into it and its turn key time :) Finally after problem after problem its feels like its coming together.

Cheers

Mr Ree

[DrNick]

Why not try the injector scaling feature in the emanage?

Put before 330 and after 475 and see how it fuels at idle. I'm not sure about the lag time, I had something written down somewhere I'll look it up, I think it was 0.6ms.

If you remember from our previous conversation we decided that the 7M injectors would probably flow a bit more with the higher 2J fuel pressure so 475 ought to do the job instead of 440.

On my side I've got everything sitting here now just waiting around to start, but I keep putting it off cuz I am using the car a lot now .... Its summer and I need the Supra to cruise to the beach with random hoochies hehe :D

[Mr Ree NZ]

Yeah im all for the random hoochies too ;)