swappng to EJ25, what problems to expect ?

[dpjef_belgium]

Hi all,
this is my first post.

I'm considering a swap from my n/a EJ20 engine (sohc) to a EJ25 shortblock. And I'm in desperate need of some info !

1. can I re-use my EJ20 sohc heads ?
2. will all other things still bolt on ? Like my intake manifold, exhaust manifold (MRT headers for n/a impreza) , oil pan.

The plan is to get a USDM 2.5 STI shortblock and run it with either high CR pistons or just with a thinner headgasket. Later, I'm adding a turbo or supercharger.

Thanks,
Jeffrey
Belgium

[dpjef_belgium]

Forgot to ask

- will the stock ECU handle the extra displacement and larger stroke ?

[JasonGrahn]

Intake manifold from a USDM 2.2L naturally aspirated did not bolt onto the 2.5L shortblock. Exhaust manifold did though. Why not just use the 2.5L oil pan and tap a hose for oil return from the turbo?

Stock ECU will most likely be able to handle larger stroke as my 2.2L NA ecu was able to handle it with minor effort.

[Matt Monson]

Read the Dr. Frankenstein thread. You will be fine.

And Jason I think you mean longblock, either that or your are mistaken. Legos. Any heads will bolt to any EJ block

[JasonGrahn]

yeah, i mean longblock. brain fart.