Before I parked the car for the winter, I had been noticing that when I WOT, the oil pressure drops from a constant of arouond 60 psi down to about maybe 50 or so. It doesn't just drop to 50, it starts at 60-65 and then starts to flutter the more rpms I go. Once it gets up around 5000-6500rpm is where it kinda just hangs around 50-55psi and moves up and down slightly. I dont think it has gone as low as 45 psi, but I am just wondering what this could be. We rebuilt this motor in July thanks to an LT4 Extreme Duty timing set failure, (yes I did say that I had of the ED set fail) as the timing chain started to come apart and sent smalls pieces of metal througout the engine. We just cleaned up the bottom end, installed with new parts listed below and re-assembled it. For oil, I have been using Redline 10w40 Full synthetic. For the winter storage, I just put in some Valvoline synthetic 10w40 and left it. I also am using a PF35L filter.

Heres a little info about the engine--
-Rebuilt stock bottom end w/ new rings, Clevite 77 main and rod bearings, polished crank journals, ARP main studs and ARP rod bolts, Mellings 10555 Hi performance high volume oil pump mellings pickup, and the stock oil pan, removed stock windage tray due to not working with ARP main studs.
-Ported heads, xe 236/242, comp r's, etc etc etc check sig for rest of details

Does anyone have an educated guess on what this might be or cause it? I am planning on doing a cam swap this spring an thought about swapping on a Canton Oil pan setup and see what that would do?? Or are my bearings giving me problems?? BTW, I believe it has done this since we got the motor going, but I never thought twice about until now. Anyway, if you can help me I would greatly appreciate it.

Brian

 

TTT

 

do you think it may be the windage tray?

At that high of a rpm the crank may by slinging enough of the oil out of the pan to cause the pressure drop.

Just an idea....

 

This is also what I am thinking it is. I also talked to a few shops yesterday and they said I need to get rid of the stock oil pan and install a Canton. I guess we will see.