Ok so I got everything together and installed in the car. I primed the motor before putting it in, it did have oil pressure as oil was coming out of the rockers. So I crank it with the fuel pump fuse pulled and after a second or two pressure shoots up to 40psi...great! So I plug the fuel pump fuse in start the car, have oil pressure for a second then its gone, car is running bad and backfiring. I shut it off within 30 seconds. After checking everything out I find that I crossed #1&#3 at the opti, switch them around and start it again. No more backfire and its pretty smooth but no oil pressure!!!! What could of I destroyed by crossing the wires on a fresh motor? I can hear that the motor doesnt have oil pressure so its not the sensor, and I'm not starting it again till I know its right.

Jason

 

All rockers adjusted right? Give us as much info as possible and this will be faster.

 

That pretty much all the info there. I'm positive the rockers are set right, like I said, I HAD oil pressure, but no longer!!!! Whats the chances of me taking out crank or rod bearings or the oil pump drive from have those wires crossed?

 

Oil pressure and plug wires have absolutly NOTHING to do with eachother... you could do whatever you wanted with the plugs and wires and it wouldn't effect oil pressure.

Oil pressure is controlled mechanicly. Lifters and rockers is what i'm thinking so far...What brand parts.. the whole valvetrain...

 

Crane lifters and comp roller tip rockers (not the pro-mags) and crane 10308 springs. Since I was getting a 'misfire' from the wires being switched, its it like denotation? That could of easily damaged something.

 

remove the fuel pump fuse and crank it. The slow crank won't harm bearings if you don't do it for more then say 30sec... just see if you get any oil pressure at all.

IF at all possible hook up a manual oil pressure gauge to the engine. You MAY have some electical gremlin.

 

Yes cranking the motor without the fuel pump nets some oil pressure (below 20psi) while before I was getting close to 40 psi doing the same thing.

 

redo the valve lash.. assuming you have adjustable rockers

I do 1/4 turn past lash

 

You have more oil pressure at first because the thick assembly lube in the engine causes it to be high until it washes out and the oil heats up. If you still have pressure, you're probably OK, but the only possible thing I can think of short of wiping out the bearings is if you had a violent enough backfire and it broke the plastic oil pump drive retainer or the plastic coupling on the pump shaft.

 

that is what I am thinking

 

Its a melling pump with so its has a metal pump shaft. I'm going to pull the intake tommorow and see what is going on under there.

 

We were talking about the stock intermediate shaft that goes from the cam drive gear assy to the pump shaft that has a plastic coupling on the stock motor. Usually, when you get the Melling replacement pump, they give you a new plastic coupling with it, but you can buy a nice ARP or other brand shaft for $15 which has a metal coupling, then is not a worry.

 

Oil pump drive is fine, the shaft its ok too. Can someone give me a run down on where all the oil galley plugs are? I'm thinking one of those are missing at this point. I can see that oil HAS been to the top of the motor and the lifter valley has oil in it, but I cannot build any pressure. I'm going to borrow a angle drill and throw a mechanical gauge on it here in a little bit.

 

After about 60-90 seconds of the drill going there was zero oil pressure. The drill was spinning like there was nothing attached to it?!? Yes I'm sure I had the primer seated on the shaft, then out of the blue boom drill twisted in my hand! Now I'm getting 60+psi on a mechanical gauge with the drill. What just went on? It was like the oil pump wasnt even turning then boom it caught. I dont want to throw the intake back on untill I'm 100% sure everything is right. I had someone crank it over while I was priming it and it kept pressure.

 

If your 383 has flat tappet lifters be very careful about cranking the engine before the cam has been broken in. If it has roller lifters this is not an issue.
Many cams go flat because of start up issues before break in.
Put a mechanical gauge on it before you sweat about oil pressure.