I know I've had tons of threads before about this, but I think that an oil cooler may take care of my problem and I'm hoping someone can verify my theory. Here's the deal:

383 LT1, brand new oil pump, stock pan: I ran this setup for about 8,000-10,000 miles before I blew it up (nothing to do with oil pressure though). Pressure would start out around 60 PSI cold, would drop to 40 PSI while cruising and 20-25 PSI at idle (800 RPM idle) once warm. I tried Mobil 1 10W30, Mobil 1 15W50, Pennzoil 10W40...it was the same with all of them.

385 LT1 (rebuilt 383 after I blew it up), another brand new oil pump, stock pan: I'm running this setup now and I'm seeing the same behavior. Again, I've tried a couple of different types of oil...Mobil 1 10W30, Mobil 1 15W50, Pennzoil 20W50, and I'm currently running Castrol 10W30 due to the cold. I'm getting the same pressures as I did before.

I've also tried a couple different kinds of filters (Wix, AC Delco, PureOne) and they all seem to behave the same (currently running a PureOne). What worries me is the 20-25 PSI at idle...I would think that it should be higher than that based on what I see my friend's cars idle pressure at (around 30-35 PSI). I'm thinking that maybe the stock pan just doesn't have enough capacity to let the oil cool before it sends it back through the engine, so it's getting thinned out as the engine heats up. However, the temp gauge never goes above 180* even in the summer heat. I know that's coolant temp, not oil temp, so maybe it doesn't make a difference.

So...would an oil cooler help me out any? I'm thinking that cooling the oil as much as possible would keep it from thinning out and I'd be able to get my pressure back. Sound logical, or am I thinking too hard? Should I even be worried? Thanks for any input you can give me.

 

Maybe your gauge is off?

 

Both of my LT-1s ran about 20-25psi at idle while stock. My camaro after being rebuilt (355) is still running around 25psi at idle once warmed up fully and runs about 50 while cruising. I'm not sure you need to be concerned...I've always understood that about 10 psi per 1,000 rpms is acceptable.

 

Your pressure sounds very normal to me.

 

Jeff i used to have a cooler on mine (stock shortblock) and when i took it off i actually saw a rise in pressure.

New motor idles at about 30ish, maybe a tad higher when warm. I do have that miloden pan on there though. Startup is 70ish cold...eeek.

No answer for you, im just talking and hoping someone else chimes in.

 

The M1 30wt.s are just barely 30wt. and approach 20 wt. with usage. Try the 0w-40 it is a better choice for the LT1 and will give you the cold weather performance you need. On the oil cooler, even with a stock stat most of us will reprogram the pcm to keep the coolant a good 20degreees cooler, run a 160 and we will keep it almost 40 degrees cooler than stock that will have a big impact on oil temps. Plus the factory cooler was there for use with dino. I am pretty confident in saying that with a low temp stat, low fan temps and synthetic oil the cooler is unnecessary, and is a restriction too the system.

 

It sounds like I don't really need to worry about it then...good to know. I'll give the Mobil 1 0W40 a shot if I can find it and see what happens when I'm due for my next oil change.

 

The stock oil cooler is actually a poor design. All of your oil is forced to pass through a small screen. If this screen was to get plugged up, you would oil starve your engine (no safety bypass).