Not for the faint-hearted, Willall Racing Engines of AU has developed a billet block for 4-cylinder 2.5L Subarus, using 6061 T6 aluminum. Potential HP levels are said to be in the 1000-1500 HP range. Cost from IAG for a completed engine is $15K. Must be an economy of scale market in the car world sufficient to make the initial machining investment. Doubt we'll see them at cars & coffee, eh? Google "Subaru billet block" to learn more.
There must be some tremendous boost to get over 1000 hp from 2.5L.
No different than those drag racing Ecotec 4 powered cars.
The STi guys are all drooling over these. Some of those maniacs are already getting 600-800 out of stock blocks on street cars, but they melt pistons or blow cases apart on the regular.