The king

Yep, used to take it for granted, but I just did a search now, and found out thats not normal on scoobs (What the f##¤ ). Not shure how its done, but Im shure planing on finding out. No 2.5s where stock with the closed deck right?

dynamix

iTrader: (3)

There is no factory closed deck 2.5 block to my knowledge.

The STi has a semi closed deck EJ257 block but as Tony says, it has limitations.

jura11

iTrader: (7)

2.5 Subaru engine are weak,you can have look here https://www.scoobynet.com/scoobynet-...-failures.html

I will recommend little bit invest to make your engine stronger...
And about the AFR look at this thread(is not subaru related,but related to Subaru tune) http://www.eng-tips.com/viewthread.c...=101915&page=5