Hey everyone,
I recently acquired some 2.5L "JDM" heads from a 2007 Subaru, make and model unknown. The heads were form an imported long block and the person who bought the engine couldnt/didnt use the heads because the heads have AVCS. I have an 04 STi body harness and ECU to run the AVCS but I cannot find any information on these heads. The casting markings on the heads are RH B 003 and LH B 003. Im pretty sure these came off a NA engine because the AVCS oil feed line on the passenger side doesnt have the turbo feed coming from the banjo fitting and the inside of the valve covers are marked NA-RH and NA-LH.

The combustion chambers look quite like the b25 but I dont know for sure if they are or if the cams/valves are the same.

My best guess is they are the same head as the b25 but would like confirmation. But if they are different, why are they different?

I am planning on doing a 2.5L build and want to use these heads with a mildly built bottom end, forged pistons, better rods and a newer crank.