okula247

iTrader: (2)

My 1jz harness already has a resistor box soldiered in because the guy i purchased it from was running Supra 550's. I cant get the 550's to run right now(emanage issues) so I want to put my stock injectors in. Will their be a problem?

short version: will stock 1jz injectors work ok with resistor box.

frankdms

iTrader: (1)

long read below. Will they work- yes, bad idea Yes. It is easy to bypass the resistor box!
Your injectors share the same power and are ground controlled at the pcm. Simply make an ugly solder connection at all the wires going into the resistor box. Remove resistor box/ 550cc's and sell to me. Hope this helps. Btw you can use the aristo 2jzgte 440cc injectors with your stock pcm + fuel controler without a resistor box. Cheap upgrade easy fit and good for 350hp+.

Low- 1.7 to 3.0 ohms (Peak and Hold Driver/Injectors)
These type of injectors and drivers may also be called current sensing or current limiting. They are more expensive and complex than saturated circuit drivers, and are not generally used with domestic production ECUs. They are primarily used in aftermarket high performance systems. Most high flow injectors are low resistance (2-5 ohms) and use a peak and hold driver to activate them. The Peak current is the amount required to quickly jolt the injector open, and then the lower Hold current rating is used to keep it open for as long as the ECU commands. These require the extra kick from the higher current to keep the opening and closing time of the injector stable at the higher fuel flow rate. With this type of driver, 12 volts is still delivered to the injector, but due to the its low resistance, the current in the driver circuit is high. How high? Using Ohms’s Law we can calculate the current rating (12v/2 ohms = 6 amps). This is substantial current flow and a Saturated Injector cannot handle it. The drivers also come in two values; 4 amp peak/1 amp hold, and 2 amp peak/0.5 amp hold.. Even though 6 amps may be available to operate the injector, the maximum it is allowed to reach is 2 or 4 amps, depending on the driver’s current limit.

Your 1jz's are*High- 10 to 16 ohms (Saturated Circuit Drivers/Injectors)
Most domestic OE production EFI systems use an ECU with 12 volt Saturated Circuit drivers. These are very inexpensive, simple, and reliable. This type of driver works by supplying 12 volts to the injectors and the ECU turns it on and off to establish a fuel injector pulse. In general, if an injector has a high resistance specification (12-16 ohms) the ECU uses a 12 volt saturated circuit driver to control it. This means that the current flow in the driver and injector circuit stays low keeping the components nice and cool for long life. Conversely, a downfall of a Saturated Circuit driver is that it has a slower response time (and closing time) than a peak and hold type. This slower time can somewhat decrease the usable operating range of the injector energized by this driver. An injector operating on a saturated circuit driver typically has a reaction time of 2 milliseconds while a peak and hold driver typically responds in 1.5 ms.

okula247

iTrader: (2)

Thanks for the Info. And i still want to keep the resistor box and 550's thats why i dont want to remove it. I just want to get the car running and later on put the 550's and some kind of fuel control in.

So you would not run it daily driving real easy for like a month or two?

frankdms

iTrader: (1)

No.

Cut off the resistor, solder, save the old, re-install later.

okula247

iTrader: (2)

ok to clarify since ive been screwing up left and right lately. cut wires to resistor,remove box. And solder the remaining wires from injectors together?