[CREWZIN]

Hate to sound like a stuck record on a single track....but were all the ignition related parts changed before or after installing the used engine? Could be as simple as what we've been telling everyone...plugs and wires. If the plugs are OEM, at 30K they could have widened to way over the .050in gap that they were probably set at. QSD pointed to the fuel pressure, but you never know wat kind of fuel was used by the previous owner. A good professinal injector cleaning might be in order. If it's running quiet and strong that's a good sign. Good luck with it.