Bigport Injector Compatability - YES have searched

[skit]

Hi all,

Time to settle the score because after tracing through lots of old posts concerning various injector types/sizes etc for 4ages, there seems to be a degree of misinformation to trawl through, & is something I fundamentally do not comprehend - so can someone please explain this to me:

I have personally removed several sets of jdm rwd bigport 4age injectors (from ae86's) which have had grey plugs, and no resistor packs in the efi harness.

I have just removed a bigport engine from an adm ae82 seca which uses pink injector plugs & has the resistor pack.

Fair enough, all the explanations I have read suggest that the pink type are low impedance & hence require the injector pack. I have inferred from this that the grey type are therefore high impedance as the jdm rwd harnesses have no resistor pack.

BUT - there are lots of injector guides out there, such as theToysport one (I have tried to attach it but can't get it to work) which show that pink and grey injectors have similar impedance (2.7 vs 2 ohm).

If so, why does the jdm rwd 4age loom not have a resistor pack? I have read everywhere that jdm & adm bigport ecu's are interchangeable, so I guess the answer does not lie there...?

I have also read that the pink injectors only came in the hybrid 7 rib bigports, which I disagree with knowing that this engine is a 3 rib & has never been removed from the car previously.

If you wonder why I ask - it is because I am using the ae82 long motor with rwd ancillaries and jdm bigport 4age loom & ecu for an engine conversion. The pink injectors are clean & I know work well, I have grey ones also but they have been stored away & will need cleaning. Hence I am considering if the pink ones are useable. Intuition says "no", but the Toysport injector guide confuses me...

Look forward to an explanation...

[Killswitch]

I too would like this clarified. I'm in a similar position.

[Mos]

I haven't looked at the toysport doc or searched for anything.. but... The JDM AE86 4AGE injectors are low impedance, with PWM current limiting by the ECU itself. This is the only ECU that I know of that does that - all other ECUs/engines that I have seen do injector current limiting either through high impedance injectors or resistor packs.
There might be a subtle possibility that there is an AE82 with low impedance injectors and *NO* resistor pack (as my AE86 had an engine loom off an AE82 with no resistor pack) however I can't confirm that as I haven't measured the injector impedance.
The AE86 current limiting was confirmed by scoping the injector signal and viewing the current through them, so consider it as fact

Mos.

[beerhead]

Yep, Mos is right. The pink injector and external resister box type looms are normally only found in AE82 secas. They're apparently the 98kw ecu version too. The loom is ecu specific, so if you run a JDM ecu, bypass the resister box or the injectors won't get enough voltage to open.

I've run the pink injectors on both JDM and ADM ecu's that don't need the resister pack in the past.