Just got my newly rebuilt 390 back in the old AMX. Fires up nice. Plenty of power.
Just when things are looking up. My oil Pressures drops off to about 5 psi after about 6 miles (190-200F).
Starts up fine about 55-65 psi cold.
Holds nice for a little while then just falls away.
Engine sounds great. Although I haven't driven it around at 5psi. I checked the gauge it operates fine. If i let it go long enough the idiot light comes on. Pulled the oil pump apart and there is some wear, but the clearances are in spec. I pulled out the Oil pressure bypass valve it seams OK, but it’s a very tight fit in the housing. The spring is new. I'm at my wits end I don't want to pull the motor again!