2G Oil pressure

[b00zt3d spyd3r]

okay so I had this problem with high idle. Fixed that by adjusting the adjustment screw on throttle body in pic. Now I've noticed my oil pressure isn't as high as it was.... Could this be because I lowered the idle speed? Or something worse? I know it has enough oil, but worried about if it's actually getting where it needs to go

 

[Cooper-97gst]

That's normal. Mine sits the same at idle. As long as it's moving then you should be fine. If your actually worried about it you need to install a separate guage to take readings accurately. I think your ok tho.

 

[curt-s]

Yeah.. dont rely on that gauge for accurate readings.
Oil pressure is directly associated with rpm so, yes, lowering idle rpm will lower pressure.
An aftermarket gauge (not getting into the electrical vs mechanical debate) will tell you what it actually is psi-wise, so you could leave your worries until you know the numbers.

 

[ThunderChild]

I do agree the stock gauges are pretty innacurate. Mine sits almost bottomed out at 20psi on my aftermarket gauge.

Not to hijack, but for those of us with an aftermarket gauge, what would a good idle pressure be?

Currently I see 45-60psi cold start, after driving it idles @ 750 and I see 12-18psi depending on oil temp. Currently running Rotella t6 10w40, contemplating switching to 15w50 after my 1500 miles is up. I'd honestly like to see closer to 20 psi.

I have an innovate mtx pressure/temp gauge.

 

[97gsxIA]

Pressure at idle should not fall below 10psi. 12-15 is normal, no need to purposely try to make it higher than that.

Oil weight should be decided on oil clearances and engine modifications. For example, my main and rod bearing clearances are looser than spec for the application I use it (racing duh) so I can use a thicker weight oil to up the pressure. But thats just one of many variables when considering oil pressure and flow.

The meat and potatas is that if you have a stock motor, stick to what the FSM tells you is appropriate for your climate conditions.

 

[ThunderChild]

97gsxIA thanks for the info. My bearing measurements were on the tigher side of factory specs, so that made me wonder of I had an ofh issue that might be causing lower idle pressure, but I had no spec to go from. I need to get a FSM one of these days.

 

[GST with PSI]

Currently I see 45-60psi cold start, after driving it idles @ 750 and I see 12-18psi depending on oil temp.

Just bump your idle a little and your pressure will probably be right about where you want it. 750 rpm is a little on the low end for idle anyways.

 

[97gsxIA]

I've experimented with idle on multiple different setups to find good target for a balance of proper ISC control, cams (vacuum), oil pressure(dependent on ofh relief), etc. And I don't think I have ever decided on going less than 900rpm on any of them.

I will say that the easiest way to fix most of those issues is simply bumping the target up as our lovely Wiseman has just stated.

 

[ThunderChild]

That's what I was thinking, it seems to be much happier around 900 rpm, and pressure picks up a couple psi.