Haltech ECU Conversion

[Ajzride]

I'm starting a thread to discuss Haltech ECUs for the Subaru powertrain. For the 2002 - 2007 WRX, Haltech offers a "plug and play" solution that allows you to plug in the Subaru WRX harness directly into the Elite 2500 ECU paired with a PD16 IO expander.

I think most 818 builders would opt not to use the plug-and-play harness because of the necessary wiring diet associated with the FFR kit anyway. Attached is my spreadsheet, which attempts to assign the IO for a typical 818 (No TGV, no stock fuel tank).

I had investigated the Elite 1500, but it did not seem to have enough IO to pull off anything but the most basic of builds. Other options are the R3 and R5 from Haltech, which offer more IO and can include power distribution. I already have power distribution and chassis wiring through my Coach-1 setup.


Haltech 2500.pdf

[Ajzride]

I did more research today. Haltech also sells a plug-and-play kit for the S3, which is the successor to the Elite 2500 (plug-and-play wiring pins for both linked below, they are too big to upload). The cost difference between an Elite 2500 and an S3 appears to be less than that of the external wideband controller, which is built into the S3. If you want wideband O2 control, then the S3 is a better value. Additionally, the R3 is only $300 more than the S3 and includes 4 High Current outputs (which can drive fans and fuel pumps), USB-C, and wifi built in. Overall, the R3 sounds like a really good deal, although it does not have a plug-and-play harness for the Subaru engine.


The R5 is the biggest ECU, which has increased inputs and outputs and might be suitable for a dedicated track build with multiple fuel pumps, multiple O2 sensors, etc. At almost double the price of an Elite 2500, it is probably not a good value for a street-driven 818 project.

S3 plug-and-play wiring:
https://www.haltech.com/product/ht-2...-harness-kit/#

Elite 2500 plug-and-play wiring:
https://www.haltech.com/product/ht-1...-wrx-my06-10/#

[DukeNeverwinter]

If you want ONE box to do the entire care with turnsignals/lights, etc. I think the R5 can do it. Yiu may need a relay or two just for lights. But it could probably do everything engine and power accessories. As in the other thread. Foe those considering. Once you get a elite 2500 and wideband and PD16(power distribution) the r5 isn't far off.