oil pressure

[Mbubby61]

What pressure should my auto-meter mechanical gage be reading.. when it idles, it drops down to like 5-8,, when it first starts it is over 20, then as it heats up it drops,,, so what is the norm,, lunati cam #81302lun,, thumper heads, 30 over on a cobra roller block 5.0. Just wanting to make sure i am not to low,, using mobil 1, 5W-30.

[blown96cobra]

That's really low. Should be min 20-25 at idle when at operating temp.

[flyin2jz]

yea 5-8 is low at idle. YOu could idle the car up a bit and the pressure will be better or add some 20/50 oil. Or you can take it apart and find the problem. Something is wrong at those pressures. Doesnt sound like you have much money in the motor, i would add the thicker oil and run it till it blows up

[INSANEBA]

Run 10w30/40 and a quart of lucas. You probably have some miles on it, and the cam bearings are a lil loose. Happens all the time, not a big deal. A motor can survive on 7psi oil pressure, so just add lucas and thicken up the oil a lil. Also, the higher idle doesent sound like a bad idea either.

[Mbubby61]

Motor does not have 2000 miles on it,, cam and heads are new. also new oil pump and pickup. it comes up when I bring up the rpm. No noise from the engine saying it is starving for oil. I switched it over from a v6 to a v8. its all pretty much brand new really.. i bought a new chrome dipstick, and wondered if it was correct. Can too much oil lower to pressure ??

[Rick93coupe]

With a stock pan you just need to put in 5 quarts, start it up to cycle the oil through the filter. Then let it sit for a few minutes to settle and mark the new dipstick wherever the level is at, as full.

[NUTTSGT]

Where all the galley plugs put back in it when it was assembled ?

[Pitbull1052]

blowncobra suggested it but are you talking at cold start up or at idle........ I never really knew it but when i just put a motor back I never really knew what the numbers on oil meant so I researched it. The first number is going to give you higher or lower oil pressure at start up so the 5w is going to give you a higher oil pressure at start up than a 10W.

[heyitsmepugsley]

i have this same problem. oil pressure goes up when driving but when you are at idle it goes way to low. but it runs flawlessly. no noise or anything along those lines. so what exactly would you guys recomend 4.5 quarts of 5w and a bootle of lucas?

[Rick93coupe]

"The viscosity grade (for example, 5W-30) tells you the oil's thickness, or viscosity. A thin oil has a lower number and flows more easily, while thick oils have a higher number and are more resistant to flow. Water has a very low viscosity -- it is thin and flows easily. Honey has a very high viscosity -- it is thick and gooey."

http://auto.howstuffworks.com/fuel-efficiency/fuel-consumption/question164.htm

That being said, a 20W-50 would increase your oil pressure. I had an engine that the lifter bores were honed and out of spec, causing low oil pressure. Going to a 20-50 oil made huge improvements in the oil pressure #'s on that motor. Give it a try.

Keep in mind that isn't a good winter oil!

[heyitsmepugsley]

thanks for the info. i will try it out.

[IWRBB]

You should see at least 30 PSI at idle. Rule of thumb is add 10 psi for every thousand RPM. So 2000 RPMs should be about 40 PSI, 6000 RPMs should be close to 80 PSI.

[full force]

You should see at least 30 PSI at idle. Rule of thumb is add 10 psi for every thousand RPM. So 2000 RPMs should be about 40 PSI, 6000 RPMs should be close to 80 PSI.

on high pressure high volume yes, standard it will not be that high...

But no matter what a good rule of thumb is the 10 psi per 1000 rpm, a standard pump usually tops out at 50 psi

[mustang_gt88]

My car idles at 25-30 psi when warm and i run lucas 10w-30

[Mbubby61]

think i will drop the mobil one,, was using 5w-30,, drop some motor kote and go back to my castrol mix, 10w-40 and see what happens.. will not be running it much in the winter,, maybe i will do a you tube video of it before and after,, watch it go viral and i end up on leno lol.. pressure,,,under pressure !!!