Oh yeah, and you didn't say what engine this is. Another thought is to make sure you didn't forget to reinstall any oil galley plugs your engine may have had, assuming any were removed during block cleaning. Oil pressure is from resistance to the oil flow of the engine, through all the passages and bearings clearances. The more loose the tolerances, or forgotten plugs, the lower the oil pressure. Ok, that gives me another thought, did you check your crank bearing tolerances with plastigauge? Did you rebuild with a new crank kit, or did you just reassemble with replacing parts, but not having things like the crank journals reconditioned with using the appropriate undersized bearings?

 

My bad, I miss read the first post Thread it is that oil pressure dropped 10-15 PSI. You need to verify oil pressure with a hand help pressure gage.

You said it was a new motor or is it a rebuilt motor? Those are two VERY different things. There are dozens of places to screw up a rebuild and get low pressure. Most common is Cam Bearings but if the assembly was not done right issue like the crank being ground on a slight taper can cause issues but should show up on the plastic gage test.

When I use to build race engines I use to double check my builds with a oil pressure primer with the engine was still on the stand. I gaged the oil pressure and compared it to other engines I build. Even the clearance in a new highend oil pump can cause lower oil pressure. I use to dissassemble every oil pump and inspect them for clearance. Yes, I have had pumps that I returned. New does not always equal good.

 

I am using a mechanical and the gauge that comes with the car and they both read identical.

 

This is 383 lt1

 

change oil filter to a purilator or a made by purilator, what oil pump did you use. from what i have read the lt1 calls for a high pressure pump and that is what i am using. i tried 10w30 and pressure was a to high so am using 5w30. with about 20k miles on new motor i am seeing 60 lbs all the time when cold, at operating temp at idle i am seeing 40lbs and at operating rpms 60lbs. imo the lt1 is intended to be a close tolerance motor so thicker oil in a new motor is not a good idea.

 

Who built the motor? How long has this been going on. There is a big different between the motor has done this since new and The motor started doing after the first time I ran it 6000 RPMs.

The first means something was not fitted right the second means something could be coming a part. Dramatic drops in oil pressure after a event (anything like over heating, racing, even a oil change) are indications of something going wrong.

As a general rule an engine needs 10 PSI per 1000 RPMs so it does not damage itself. I use that number when looking to see if a motor should be repaired or replaced. A motor can last a long time once it dips down to where you are at but if it was mine it would be coming back out to figure it out what was going on.

 

Being a 383, was this a complete engine rotating assembly "kit"?
And don't forget my other two questions that haven't been addressed.

 

i would add to my last post, high pressure oil pump not a high volume oil pump. they make a high pressure high volume pump that i would not advise you use in a new or rebuilt engine. lol, another question to add to the barage,,, was the oil cooler removed?

 

Basically I have to take the motor out and get it checked over again everyone would agree?

 

I don't, If I just installed it and I was sure there was nothing else going on then I would pull it back out. There is no way we can answer that until you answer the above questions.

Who built it?
What was done?
When did the issue start?
Who will be doing the tear down? (if not you then get them involved BEFORE you remove it)
Is there any metal in the filter?