Overheating 4 cyl, Help, please look again!

[joetoken]

I tested the fans and they are working correctly, thermostate is opening, ie upper hose is cold and then gets hot as lower, it just seems to be generating a lot of heat, it will overheat standing still now if i hold it revd to 3000 for about 5 to 7 minutes, I am starting to wonder about the oil pump or perhaps a clogged oil gallery, they funny thing is it runs ok until it heatus up, I guess I am goign to have to tear it down, at least to the long block, It really doesn't make sense, oh and yes it will boil over through the bypass on the overflow

I am at a loss, I hate to start tearing it down, I know it will end up being something stupid

I pulled the trainy on it once and it ended up being front wheel bearings, anyway I will let you guys know, thanks for the input

[joetoken]

Well, I pulled the plugs and they were white so I changed the O2 sensor, I checked the cap and rotor and the contactor on the rotor was loose so I replaced that, still no joy, it gets about 3/4 of the way up on the gauge and holds now instead of going almost to H,

I purged air for a really long time this time, like 30 minutes idleing with the cap off

any ideas on why its running lean or what to check? I am beyond puzzled, none of the normal stuff seems to be the issue, I am going to again pull the radiator and make sure there is nothing restricting the flow. however, that would not make it run lean.

the only thing that is not stock on this car, which is a 92 with a 4 banger,
is the air intake, I have a cone filter connected to the MAF

other than that it is bone stock

Could a bad Catalytic converter cause it to overheat, it is the original, they do not test emmsions here

also, car has developed a fairly rough idle, doesn't miss or anything, just idles rough, other than that it accelerates fine and runs well, just runs hot

If anyone has any ideas let me know