Long story short, I picked up a dirt cheap (but clean) N/A '05 Legacy that had a "broken timing belt" (it actually was a sheared tensioner bolt). I pulled the heads and eventually realized the car has the wrong heads. It's got dual port heads but the single port exhaust. So either this thing had a head swap at some point, or the entire motor. I'm not sure which.

The pistons are what gets me though. I was a subaru tech in the mid '00's and I don't remember the pistons looking like this.
https://i.imgur.com/CVUdYSh.jpg

What's with the dual valve reliefs? At first I thought the valves made those marks but some of them didn't even hit (there was only 4 bent valves in total). Besides they're all carboned over. If the valves hit them they'd look fresh.

So... what am I looking at here?

If this is how they normally look then I'll just slap the correct heads on and call it a day because the rest of the motor is spotless. AFAIK pretty much all N/A EJ25 blocks are interchangeable anyway right?

Well , that’s a new one to me... not Cali Spec pistons , and single exhaust port on each head would be Cali spec as well.

I think that has to be some type of Jasper , ATK, Fed/Mogul reman shenanigans.

So those are non-cali spec pistons? What's difference with the Cali spec ones?

The heads are dual port. They've been running it like this:





So it seems the whole motor was replaced with a non-cali spec one. So the big question is there any reason I can't just use this short-block with cali-spec heads?

Just something I've found. I was looking for a picture of the difference between CA and non CA pistons and found this:

https://www.partsgeek.com/catalog/20...iston_set.html

So if this is to be believed, Non-CA means dished pistons, CA means non dished pistons. Which would mean that I do have CA pistons, but that doesn't explain the extra set of valve reliefs that just straight up look weird to me.

Ok another update. Someone on reddit said they look like IKON pistons, so I looked it up, and holy **** he's right.

https://i.imgur.com/iYhcqEN.jpg

That would be really odd for high performance forged pistons to make their way onto a bone-stock automatic N/A legacy. I'm going to guess that these are just regular aftermarket cast replacements. But the thing I learned is that the 8 valve reliefs are so the pistons can be used on either side. Never seen some **** like this before but I think it's ok to use.

Gets even weirder. I just looked at the engine again. It's an EJ20.

I'd say that's your problem right there!

I can't even fathom how bad it must have run with that exhaust setup!