Boring and mostly self-indulgent post. Enter at own risk.
I finally got off my arse and bought a new engine for my Impreza. I’ve been planning and researching an engine swap for maybe two years now, or maybe since I bought the car new back in 2000. I know I’ve asked here about importing complete engines or longblocks before.
My Impreza is a bit of a hybrid, being assembled in Taiwan out of parts that are about 90% Japanese in origin. It’s bizarre in that as far as the engine specs and emissions paraphernalia goes, it’s very close to the JDM version. What’s odd about that is that the car is naturally LHD, so I guess Ta Ching must have had some fun shopping through the corporate parts bin at FHI…
After 135,000km of mostly trouble-free motoring, I need more grunt than Ta Ching saw fit to offer. I’ve thought about either blowing the original engine, or swapping in a complete turbo drivetrain, but the first idea is bad for a daily driver and the second is more money than I want to spend. Not to mention that turbo lag sucks donkey balls in Taiwan traffic.
Anyway, what’s problematic about this swap is that the 2.5 liter naturally aspirated engine is almost unknown in Japan, but very common in the US. However, the USDM car has a bunch of emissions type junk on it that the JDM models don’t, like sensors for fuel temperature and tank pressure, and controllers and solenoids for all sorts of purge canisters and recirculation devices, extra catalytic converters and more sensors to check on them. So, a big headache for me is that I can get a USDM engine and ECU, but my car lacks all these (useless) peripheral devices and that’s for sure going to have the ECU bugging out and throwing all kind of trouble codes. I don’t know about you, but I hate driving around with the CEL on.
OTOH it’s going to be a PITA trying to figure out which exact year and model JDM ECU will match my mix of peripherals and the engine series I want.
There were some 2.5 liter Foresters and Legacys imported into Taiwan, maybe about 5 in total and as rare as rocking horse poop. No guarantees on use or condition. :s
I decided to fit the 2.5 engine and run it off my original 1.8 ECU. There’s no way in hell my stock ECU will just magically hit my target AFR running injectors almost 50% larger than it will think are there, so some tweaking is required.
JDM SOHC Phase II EJ25 longblock and timing belt.
USDM EJ25 fuel injectors.
TDM EJ18 intake manifold and throttle body.
TDM EJ18 sensors.
TDM EJ18 ECU + Greddy Emanage piggyback engine management.
Greddy PC support tool for tuning sensor inputs, adding injector pulse width and modifying ignition timing etc etc.
WRX brakes front and rear.
KYB AGX adjustable sports suspension.
STi v.5 springs.
Clarion/Infinity/Image Dynamics audio with two amplifiers and 900W total RMS power.
Improved sound deadening and acoustic damping.
I saw my new engine today, fresh off the pallet from Japan. It’s beautiful, brand spanking new, never been run. There isn’t a speck of soot in the exhaust ports. I got a longblock only, so the water pump, pullies, belt tensioners, intake and all ancilliaries have to come off the original engine. It looks exactly like my original, except it has the telltale engine code, and no engine serial number, since it was never installed in a vehicle.
Hunh? That’s right. Not even intended for that either. Subaru sells engine direct to builders of experimental aircraft, which is what this one was originally destined for.
Rather than test too many things at once, I decided to install the engine management first, get that up and running, and then let my buddy install the engine. I no longer have time to spend a week in the shop hoisting engines… My day was spent on my knees, head in the passenger footwell cutting and splicing into the factory wiring loom at the ECU. There’s a lot of wires in the bundle and it’s easy to make mistakes. I’ve spliced in with extra OEM style connectors so I can rip it out again or isolate particular wiring groups easily should I need to troubleshoot the install. Thumbs up to Taiwan for these kind of supplies being available right off the shelf in electronics alley.
Finally got the new wiring harnesses all labelled, soldered and plugged in after a 7hr slog. The engine started on the first try, which is nice, but now I’ve got some error codes from the emanage and the TCU, so the fat lady hasn’t sung yet. Got to try and fix those issues tomorrow with some firmware updates and some different approaches with the update and parameter setting procedures. I’m an oldskool tune by jets and needles carburettor guy, this tune by laptop stuff is all new to me. New millennium starts next week.
Cliffnotes: Bought new (upgrade) engine for car, very excited.