I just realized today that the VIN for my 95 Legacy L is BK6.
I know as a general rule 4 = 2.2L and 6 = 2.5L:
http://www.sl-i.net/FORUM/viewtopic.php?f=41&t=8058
But I guess since in 1995 they didn't even offer a 2.5L the engine codes might have been different.... just thought it was interesting.