Oil Pressure question Options

[hars914]

I just installed a front oil cooler using -12 lines from engine to cooler.I test drove the car Sunday for about 5 miles. I noticed my oil pressure at speed was around 50 psi
and at idle around 20 psi. The oil temp while driving was about 170 or so.
Before I installed the cooler my presure was around 20-25 psi at about 2000 rpm
which I think is normal. The motor is new with around 1100 miles and does have a HD oil pump.I also use 20W-50 oil. Is this high pressure a problem or not???

[ArtechnikA]

/4? /6? /4 i'm guessing due to your mention of the 'HD' oil pump. (/6 guys tend to use numbers like '964' or '930' ...)

most /6 guys would kill for 20 psi at idle! (i wouldn't, but i'd maim somebody - who you got in mind ?)

temp looks good if a little low (but i don't know your ambient, and some think my preference for 95C oil 'excessive' -- it's your engine - run it where you want ... i want mine at 95C). you didn't mention what rpm 'at speed' was but 50 psi sounds good, certainly nothing i'd classify as 'high'. IIRC 'The Number' is something like 10 psi/1000 rpm.

[lmcchesney]

Speaking of oil temp of 179°F. Does anyone have a relationship of temp monitoring variance. If you oil temp is 170° in the external oil lines, what does that estimate the CHT to be. Is there a linear coorelation?
Thanks,
L. Mcchesney

[Dave_Darling]

The pressures sound fine to me. As a rule of thumb, you want at least 10 PSI per 1000 RPM (up until the pressure relief valve opens). Below that is a problem, above that is not--within reason. Sounds within reason to me, though others with more engine internal experience should be believed over my opinion.

There is very little if any correllation between CHT and oil temp. CHT is primarily load-related, while oil temp is primarily RPM-related.

--DD

[hars914]

The motor is a 4 cyl. built up to 2.4L. I figured the high pressure would not be a
problem since higher is better than lower. I was around 50 at 2000 or so RPM.
Just wanted to check. I will see how much it drops once the temp. builds
up and thins the oil.Thanks guys.

[roundboy914]

This thread got me wondering.
I have a new 2.0 TIV with a high flow oil pump, and a front oil cooler. At idle i also have around 20 psi, but this weekend, at highway speeds (80 mph), turning around 3000 rpm in 5th, i had like 70 psi of oil pressure. Is this too high? the temp guage is stock, and is right in the middle. Outside temp was 80+ degrees, so it was not too cold.... just wondering.

[machina]

Seems to me that any additional elements in the oil system add resistince to flow and therefore increase the oil pressure.

Adding all those lines with elbows etc, the cooler, thermostat add resistance to flow which equals more pressure.

Too much pressure in these motors makes for more oil leaks. I don't think you have a problem, just a result of adding the system.

For pluming systems, you calculate loss in flow for every elbow 45, 90, etc. Then add losses from the length and type of pipe and of course the amount of head or drop in the system. I don't see why it is any different for an oil system, accept for maybe the change in temperature and viscosity.

dr