That's a Phase I EJ25 DOHC. All EJ25 equipped Subaru's between 1996 and 1998 have that exact same engine, and some in 1999.
There's two different style timing belt tensioner mechanisms, but otherwise everything else is the same. Pretty much on way to tell which tensioner style you have without just looking. You can pull the drivers side timing cover to get a peak at it....well in normal engine without all that plumbing in front, yours might be trickier.
It's an interference engine, if the timing belt breaks the exhaust and intake valves are going to collide and cause damage.
Not sure exactly what you're looking for but maybe that helps?
Thanks Gary, you answered my first and biggest question right off the bat (ie. what is this thing?). Based on that hopefully I can find some service manuals. I know it's highly modified (running a Stinger EMS and with the single Turbonetics Turbo) but that should still help. It's currently running great, I just want to be able to keep it that way.
Up until now I've been running Volkswagen powered buggies (and rebuilt a couple engines from the bottom up) and based on that I can't conceive how exhaust and intake valves can collide. Going to have to find some engine diagrams.
ETA: OK, found a diagram and see what you're talking about. I'll be sure to keep a nice solid belt on it at all times!
Edited by Speedbuggy, 07 July 2010 - 09:55 AM.