Hi all, just wondering what everyone knows about the JDM EJ25D, apparently also known as the EJ25DE.
This started about a year ago when I accidentally swapped one into my 98 OBW. How did I accidentally swap in an engine? I bought a 99 Legacy out of a field and knew the 99 EJ25D was different and basically a factory hybrid engine, phase II block with phase I internals and heads, so I just attributed all of those to being a 99. At the time, this was the second/third legacy motor I've pulled. It wasn't until I was putting the timing cover back on that I noticed the import sticker.
Visual differences:
-valve covers marked "4 CAM 16 VALVE" and with lines, similar to late EJ22Es
-turbo water pump w/ aluminum housing coming out the front of the pump rather than the side
-different timing cover with brackets (for O2 sensor wiring?)
-flat top pistons with valve reliefs
-threaded holes near the spark plug boots, presumably for coil-on-plug
Pictures: (apologies, didn't know I was looking for anything unusual at the time so not focusing on anything, how I missed the import sticker is beyond me, it's visible in the second picture above the right intake cam sprocket area)
I have no clue what it came out of or what year it is, though it had a single piece timing belt tensioner so 98 maybe? Also, since I pulled it out of a USM Legacy that had been using it for quite some time, I have no idea what mileage it has or what manifolds it came with, but it did have EGR.
I found somewhere, I can't remember where, that the JDM motors were rated at 175hp, 20/10 up from USDM 1996/1997-9 respectively. I'm assuming they're higher compression with the flat top pistons (since Japan doesn't have the crap gasoline that America does) but I've been running mine on 87 for 11 months/16k miles without more than the normal amount of piston slap for an aluminum engine that sat in a field for 2 years.
Currently burns 1/1.5qts of 10w40 per thousand miles, though that probably has to do with manual trans and a 20 year olds driving habits. And hills.
Does anyone have any more info on these? More out of curiosity than anything, since I've been driving for a year without issue. Found a TON of info about the different EJ22/EJ25D motors in a frankenmotor thread (for if/when the oil consumption gets too bad, the original motor in my car lost compression through the rings at 240k) and wondering if there's a similar wealth of info on these? I'd like this to be a go-to thread for anyone wondering, since I can't seem to find one, just "is the swap possible?"
TL;DR: Is JDM really better or is it worse, and how so?
I know asking if an EJ25D is reliable is like asking if I can breathe underwater, but still. 20 yrs old, 4 owned cars, 4 motor jobs in my garage. Makes me think after a while lol...