see the thing is when you rev it to 2k the noise gets kinda quiet and thats when the oil pressure is at 40psi..

 

UPDATE: I installed the stock replacement oil pump with no shim and used the oil I had in before. I got about 35psi at idle. I didn't run the motor too long because I haven't finished putting it back together. I thought the oil looked alittle thin even though I just changed it a couple weeks ago. So I went and got some regular 20W-50 oil from the local store and put it in. I got the same results. I don't want to admit it, but it sounds like I may have some bearing damage. The thing that gets me is that I don't know what may have caused it. I know it is a real pain in the butt to pull the oil pan off with the engine in the car, but I may have to do that to see what the bearings look like. I know the lower volume pump will make alittle difference on the pressure. BTW, I compared the HV pump HP spring to the stock pump and they are identical. Any ideas?

 

high VOLUME is just that, high volume. the pressure may be the same or slightly less, but the pump will more MORE oil. i'm guessing the melling HV pump is ported or something, but uses the same spring as stock. using a shim/stiffer spring will elevate the pressure, but there is no other way to increase the volume flow.

 

Well, I have decided to pull my oil pan and check all the bearings. I just came to it that I rather spend the time and check it out for myself than assume and having to rebuild a motor in the next few months.

 

Well, the pressure was alot higher when I first got this motor running and it has progressively gone down since about October/November time last year. The higher volume should have kept the pressure up unless there is an added clearance that is allowing the oil to flow out without building up pressure. The grooves in the pump could have caused some of it, but with a new pump on performing the same way the next in line is the bearings. My hopes are that the crank pins and rods are not mis-shapened to require machining. If the bearings look abnormal and the steel parts are good, I will throw a set of new bearings in. I will know more in a few hours.

 

You probably pumped the pan dry with that pump and pushed air in the bearings. You have damaged bearings. High volume means just that. The pump will flow more oil so it needs more oil available to feed it. You would have been better off with a shimmed LS6 pump. Never use a higher volume pump unless you have oil available to feed it.

 

Thank you for the response. I was hoping a serious engine builder would chime in. It was weird that I actually had almost 7 quarts of oil in my pan (don't know why) and it still did had some oil pressure drop. I was concerned about not getting enough oil to the bearings, that's why I got the hi-volume pump. I figured with my power goals I would need it to keep the motor alive for a long time. So you think the replacement pump I have with shims will be enough?

 

in order to "pump your pan dry"
you would need to be very low on oil and be at high RPM
and still you need to imagine having all you oil sitting in your heads,
witch is hard to visualize because your lifters can`t possibly pump
that much oil to the top of you engine without it
draining back down to the pan.

 

You have a point. My LOW OIL light system still works and hasn't came on. I couldn't go any further tonight because I am by myself and everyone else has a regular job. I will definately know the conditions of my bearings tomorrow night.

 

OK check these out. I pulled out all the rod bearings and two lower main bearing caps. The first one are the mains after that the rod bearings in order. It is alittle inconsistant on what has happened. What do you guys think?

 

Here are the rest:

 

Some of them look pretty bad. It looks like you need to tear it down and rebuild. Good luck.

Bill

 

There are no scratches on the crank journals so I am thinking about just getting another set of bearings.

 

Have you checked all the mains???

Shane

 

I talked to my local speed shop and the machine shop that did the work. It turns out that the bearings are Clevite 77 P-series bearing which are more used in street motors. They both said these bearing surfaces are softer and most likely didn't handle the 16psi of boost. They also agree that most of my oil pressure loss was in the #3 bearing since it showed the most wear. It would also explain the slow reduction of pressure over time.

 

One more thing going to your original comments run a wix not a FRAM orange can of DEATH!!!!

 

I don't see what that has to do with it. I have ran Fram oil filters in all my cars.

 

The pump and engine likely injested some bad stuff like crud and metal chips from the machining process. Was this block properly cleaned and scrubed after all the machining was done?

The best filter in the world will not help if the block was not cleaned properly after machining. Anyway, I use Fram filters too but I have heard from many they SUK.

 

OK, I know the routine for building/assembling an engine and with this one I took my time. I trusted the machine shop to get me the proper bearings for this motor and they screwed me. I am convinced that the bearings that was giving to me to be used were not intended for the amount of abuse that I put them through. The pump could have ate the some of the debris, but the filter caught them.