is my oil pressure acceptable?

[Anonymous]

'66 stang, 200 engine, fresh (supposidly) long block with 3000 miles on it.....

dash board oil pressure gauge at middle of range or less, new sending unit made no difference, so i hooked up a mechanical gauge temporarily.

below are the results, relative to a 65 degree day, after 30 mile drive, engine normal operating temperature (160 thermostat), fresh oil change with 15/40 valvoline:

45 lbs in park

39 lbs in "drive"

50 lbs at 1300 rpm.


do these numbers sound reasonable????

 

[BIGREDRASA]

Those numbers should put a big smile on your face. If anything, they're a litte high. With such a fresh engine, you should switch to 10W-30 synthetic when changing oil at 5000 miles.

 

[Anonymous]

thanks for the feedback...........used the 15w40 b/c it was at hand when i changed the oil at 3 am ( i work wierd hours!!!)

why does the factory oil pressure gauge read so low? any way to calibrate it to read higher?

 

[BIGREDRASA]

Factory gauges are not bery accurate.

 

[Anonymous]

My motor was rebuilt 3 years ago. I have been running 30W. Is it OK to switch to synthetic 10w30 now? In the whole 3 years, the car hasn't been driven over 1500 miles (if that!).

 

[BIGREDRASA]

The only precuation in switching to synthetic is to make sure the engine is broken in on regular oil first, otherwise the rings won't seat properly.

 

[XFlow_Fairlane]

I like to run a aftermarket gauge because of this. also it will show a low oil condition sooner.

nick

 

[Anonymous]

I have a 27 year old 250 engin it likes to run at 72 lbs at 2900 rpm 67 at 1500 rpm a 350 chevy will run at 31 lbs at 2000 so thats real good

 

[BIGREDRASA]

It's not always good to run too much pressure. That can damage seals and cause leakage. It's flow, not pressure that lubicates. (I used to be hydraulic technician in the Air Force during a prior life. ) Pressure is a result of the restriction to flow. In lubication, you need only enough pressure to ensure flow to every nook and cranny. A thinner/lighter oil that reaches all parts on startup (provided it has sufficient film strength to prevent metal to metal contact) is better than a thick oil that requires pressure buildup before it can flow to all parts. I use 10W-30 Mobil 1 Synthetic myself, and don't worry about the exact pressure readings. That oil lubricates everything, even seeping through the head gasket and removing the paint off the side of my engine block.

 

[addo]

I know with some of our local GM engines, if you ran a HV pump without restrictors, it could dry the sump almost. All the oil wound up in the valve cover. :roll: