Did you do a compression or leakdown test when the engine was together BEFORE the bearing issue? If not, the current ones only show what you have, not a meaningful comparison.
Compression and leakdown, if it is as even as yours is, has nothing to do with the unbalanced mixture issue you are currently experiencing. Let's assume for now that the long block, and cam timing are fine, and figure out what is causing the unbalanced fueling issue.
Since our normal, non high zoot engines have only one O2 sensor, it can only read the AVERAGE of what all of the 6 cylinders are doing.
What can affect this unbalance?
Individual injector filters
Crappy injector(s)
Restrictions (junk or corrosion) in the fuel rail.
Bad injector (leaking or under fueling)
Corrosion at the injector power plug(s).
High resistance or intermittent connection in injector individual wiring harness
Regulator diaphragm going bad, therefor changing/ fluctuating fuel pressure
Partially or intermittently plugged fuel return line (could be in tank, connection hose at the tank, or in pump/sending assy.
Fuel pump intermittent power wire or relay/ ground.
Bad/intermittent power or ground(s) in injector harness/plug in.
I would: connect a fuel pressure gauge at the test fitting on the rail. Is it consistent? Moves around?
Remove the fuel rail, blow it out, and put it in carb dip over nite or longer. Blow it out again.
Disconnect the return line, blow it out, (disconnect from tank) and or run a length of hose in a bucket and see if it has a steady return flow.
Have you replaced the fuel filter recently?
Blow out the fuel lines individually from tank to filter, and filter to regulator.
Read the pump voltage at the TANK while running or key on/engine off.
Rig up a "T" in the return line off of the fuel rail, pressure there should be minimal.
Any electrical intermittent to the pump or grounding, pressure or return line partial restrictions, or regulator/ filter intermittent restrictions will cause the computer to "chase its tail."
Start with the easy ones first.
Pack a lunch, and Excedrine, you're gonna need it!
GOOD LUCK!
Keep us posted.
TIMINATOR
