normally during idle i was 40ish or slightly above that...at wot it moved but not like the high numbers you see around here...now just the other day i felt and heard a difference in my car so i looked at my press. it seems to be in the low 30's now. Does this sound like it might soon become a serious issue. Im not to worried if it is 'cause it'll give me the excuse i need for my SO that it's time for a good rebuild....thanks for any input

 

Have you checked the oil level?

 

Oil pressure seems to be a somewhat more common topic these days on here. Now let me say that Im no proffesional engine builder but I have built a few over the years and consider myself to be a fairly knowledgable mechanic, not to toot my own horn. Someone recently asked me if driving their car with just under 30psi oil pressure at idle would hurt. I told them absolutely not and I will say it again. I told them even if it dropped to 15psi at idle then it would not hurt anything. Now if it did drop to 15 a idle there is probably a problem since most of us know that these cars make alot more than that. Maybe oil pump, maybe oil pump o ring, maybe bearings. If bearings are worn it wasnt due to not enough oil pressure if you have 25-30 at idle and 50 at wot like the person I was talking to. Just for the record the manual states the following :

@1000 RPM ------- 6 psi minimum
@2000 RPM ------- 18 psi minimum
@4000 RPM ------- 24 psi minimum

When the specs give the minimum its basicly stating how much oil pressure is needed to prevent metal to metal contact. As many members may or may not know, a pressurized oiling system is intended to keep moving parts "suspended" in a film of oil. Just because the crankshaft is turning in the main bearing doesnt mean that its rubbing the bearings. It is SUPPOSED to be seperated by a layer of oil provided you have enough pressure for the oil to be forced into the tight clearance of of bearings, etc.

Alot of people just dont understand how much say 20lbs of oil pressure is. That is alot.

The only reason I went through the time and trouble to post this is because I want to ease peoples mind that are nervous about overhauling their shortblock. One of my friends that expressed concern about his oil pressure I could tell was very worried.

Let me close by reminding people that this is the internet and folks always seem to gain knowledge when staring into a monitor and that opinions are like, well, you know.

 

Exactly what mine did, mine seems to be back up now though.

 

LS1's don't seem to be prone to sludge buildup, but if yours is, there may be some sludge down in the oil pan that's partially blocking the pickup screen. When you go to higher rpms, the pump sucks oil harder and will sometimes suck that bit of sludge onto the screen, thus either reducing pressure at higher rpms or making it stay the same as idle. If you or the previous owner wasn't real good about timely oil changes, sludge will form.

Jason

 

Full- thanks for that reply, so i guess i wont have to worry about it for now , ill just have to find another reason for a rebuild..lol...99 ta, i'm real good at checking my oil level...but thanks that was a good thought..99ss, i cant say much for the prev. owner looks like he did things great(thanks whoever u r) but for me i just got done doing a royal purple change less than 500 ago so ill be on it from here on out...thanks eveyone

 

Mine drops at higher engine temps. I swapped with a TSP ported pump and heavier oil, but it still drops with higher temps. I just think as long as it doesnt get real close to the red ill be fine. Its wierd though how the ls1 has ongoing complaints with this. It may be due to the aluminum block causing greater clearances once it gets hot and the journals expand causing a loss of pressure... just my guess...
Wes