383 oiling problems

[RabidScott]

The 383 in my Model A has a wierd oiling issue.  When I fire it up, all is good.  Good oil pressure, no noise.  After running it for a while, when it gets up to temperature, at idle the oil pressure drops real low, and I can hear lifter noise, like they're ticking.  Any suggestions to the problem, other than it's stuck in a Ford?   

Little background on the engine:  '69 383 Magnum, had excess crankshaft endplay which necessitated replacement of the crank and bearings.  Cheap-o 284/284 cam and lifters.  Aluminum flywheel with Centerforce goodies.

[Challenger6pak]

As your motor is getting hot you are getting more clearance somewhere.  You can check your oil pump easier than the bearings.  I would check it first and then check your bearings.  You never said if you did cam bearings with the rebuild or not.  You can loose oil pressure there also.

[Stacked440]

If your 383 has a great deal of slop in the lifter holes you will have pretty poor oil pressure.  Maybe once it heats up the oil gets to thin to lubricate it effectively.

[Moparal]

Sure sounds like main bearings. Have you cut your oil filter in half to see if you have any brass or copper in it?   Did you clean every orfice and oil passages with a wire tube bristle ? Did you use the same oil pick up tube?   Just wondering.  Aluminum flywheel I think means a harder babbit bearing needs to be used. Not sure with the aluminum wheel. If your rod side to side clearances is over .030 total or .017 each, it will have poor pressure too. Did you re condition the rods?  All your dowel plugs tight?

[Challenger6pak]

Do you have an oil pressure guage on the motor or do you feel pressure is dropping because the lifters tick?  Lifters will tick if there is a blockage in the motor.  You can still have good oil pressure and have the lifters tick with a blockage.  How long has your motor been rebuilt?  Is it just broke in or does it have several thousand miles on it since the rebuild?

[Chryco Psycho]

Possibly it is just the oil pump , changing the bypass spring to a black spring [approx $5 from Mopar could fix the problem

[moper]

Has it always done this? How many miles on it that way? Standard or HV oil pump? (the std one is about 1.25" thick from the block flange to the top casting, the HV isa about 1.5" thick there) You should get yourself a gage (preferably a decent one..not the cheapo 2" ones) to see what it really is doing. Could be nothing. Could be serious. If it's a HV and it has that issue, that's bad. If it's a std pump, at idle, it's not bypassing due to pressure, so upgrading the bypass spring wont help. You could just install a new HV pump if it's standard, but that may not do much more than mask the problem. A good oil gage will tell you what the pressure is at idle. Thicker oil may also help if you're running 10W oils.