i hope thats all this is, and it all started cause i changed the plenum gasket. ill never do that again lol

 

what would i have to rebuild if the pressure is really low??

 

I would do a minimum of rod and main bearings. (which you can do without pulling the motor) Much beyond that, and you would have to tear the engine down completely. If you wanna get the berserk, you can spend as much, or as little as you like. But, figger some machine shop time in there as well, and what they have to say can boost cost. (things like the cylinder bores being out of spec, so you need to bore it out, which means new rings, and pistons......)

 

I think you may have dropped some debis into engine while doing plenum.

Pull pump and see what is wrong. Then pull main caps and check for damage. Put back on and torque correctly if they are good. Then pull a couple rod caps and check. Don't mix them up (or the mains) and put back on same place. If there is no damage or scoring, you may have gotten lucky. Make sure you clean everything out of pan and anywhere you can wipe down.

You have to find out what happended to oil pump. Can't afford to just guess. If you are wrong, engine will be toast, and as Hey You said you will have to rebuild if you don't damage it beyond rebuildable.

I don't recal spec on oil pressure, but I am around 45-50 minimal. 20 is way to low as mentioned by others.

 

my oil psi problem all started with me doing the plenum too. i still had somewhat decent oil psi, but would steadily drop after a bit of driving. i have since replaced the oil pump and pick up tube, and the tube was the culprit. it was clogged to hell and back, and was so clogged it was sucking in the screen.