Help - oil pressure / flow on engine first start.

[JonE]

I'd like to know the proper location for Neil's brass dwarf. Do they have any purpose or can we omit like the oil baffles?

[Ruairidh Dunford]

It’s certainly not a big problem.

[circeonya@hotmail.com]

I have the opposite issue in my recently aquired RN, I have more than 10 PSI plus even when warm. At turn off the pressure dissapates slowly so I think that symptom rules out any issue with the pressure relief vave setting.. It has the high capacity sump. I have checked the squirters are clear. The last person to carry out any work on the engine is now deceased but I do know he had a mod for the oil pump and did something at the rear camshaft bearing to increase oil pressure. I know this as he and I rebuilt the engine of a 1935 rodster I had a few years ago. The mods did not seem to make much difference to the oil pressue of that engine. I have driven this car less than 150km but it runs nice and sounds fine. Should I be investigating furthur?

[Colin Cooke]

There are 2 different types of oil jet. I built an engine with the smaller holed jets once, and went for a 20 mile test drive in minus temperatures. I assumed that the engine had never warmed up properly (the driver and passenger certainly hadn't), but it turned out to be the wrong jet size. If I remember correctly, the oil pressure settled around 10psi.
I can't recall what the right and wrong sizes were, but hopefully someone will come up with the correct information.

All the best,
Colin

[Terrytuned]

Colin the three bearing oil jets are smaller bore than the two bearing jets to try and give more oil pressure to the centre bearing. Terry.

[JonE]

so out of interest, what would that do for the longer term... more pressure on the cam supply positions, and the oil squirted further and slightly faster?
Would it actually create a friction that would impinge on bhp like the c.1bhp lost from driving the mechanical fuel pump etc??

[Douglas Alderson]

Slightly different issue but oil pressure related. Engine built 5 years ago with external oil filter and enlarged oil pump all works ok and engine raced.  Oil pressure cold over 10psi when warm at tick over 2psi. 

Just started the car and pressure over 10psi cold and stayed there when warm.  Checked the jets and I am sure they were clear pressure now 8psi when warm.

Reading Jon’s comment re too much pressure, but presumably it could be a case of a high oil pressure reading might be a restriction after the oil guage so starvation on the engine.

Oil filter change and oil change due hopefully it fixes my high oil pressure.

Any thoughts

Douglas