Can hot weather cause lower oil pressure even when oil temp is the same?
#21
Fanboi
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Re: Can hot weather cause lower oil pressure even when oil temp is the same?
And to say that a random 10 psi drop in oil pressure at idle "doesn't make a difference" is foolish. All things consistent if your idle oil pressure suddenly drops 10 psi something is up. In this case the K&N I had in before must have been damaged when I hit the chunk of concrete. Swapping in the M1 filter just kept the pressure at idle down. Going back to a new K&N explained the change.
When your oil pressure gauge is after the filter adding restrictions results in a lower reading. This may not be the case if your pressure sensor is right after the pump, but that's not the case in a LSX.
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Re: Can hot weather cause lower oil pressure even when oil temp is the same?
I understand what you're saying, and I agree that the pressure is still perfectly adequate at idle...
#23
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Re: Can hot weather cause lower oil pressure even when oil temp is the same?
just so you know i looked at my gauge today when driving.
At idle with 220 oil temp...it was 25psi. 5w30 and ac delco filter(if i remmeber correctly)
I use to read a little higher before my old sender went bad. Also lookin at your tach, your car idles higher then mine. Still on the cam tune?
At idle with 220 oil temp...it was 25psi. 5w30 and ac delco filter(if i remmeber correctly)
I use to read a little higher before my old sender went bad. Also lookin at your tach, your car idles higher then mine. Still on the cam tune?
#24
Re: Can hot weather cause lower oil pressure even when oil temp is the same?
LOL I'm gonna do a engine rebuild.
Anyways back on topic, sorry for thread-jack.
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Re: Can hot weather cause lower oil pressure even when oil temp is the same?
Damn, read this thread too late, my first thought once you said you changed the oil was that it was the new oil filter affecting the pressure. Anyway, glad you got it figured out.
#26
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Re: Can hot weather cause lower oil pressure even when oil temp is the same?
just so you know i looked at my gauge today when driving.
At idle with 220 oil temp...it was 25psi. 5w30 and ac delco filter(if i remmeber correctly)
I use to read a little higher before my old sender went bad. Also lookin at your tach, your car idles higher then mine. Still on the cam tune?
At idle with 220 oil temp...it was 25psi. 5w30 and ac delco filter(if i remmeber correctly)
I use to read a little higher before my old sender went bad. Also lookin at your tach, your car idles higher then mine. Still on the cam tune?
Also... to be clear, the pressure figure never bothered me, just the delta. In fact, if I put a new cam in the car this winter I'm going back to a stock oil pump as the high volume on isn't needed anymore.
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Re: Can hot weather cause lower oil pressure even when oil temp is the same?
Where does the pressure gauge sense pressure? It's not directly off the discharge of the pump is it, seems like there are better places to measure at...
#29
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Re: Can hot weather cause lower oil pressure even when oil temp is the same?
Pressure sending unit is at the back top of the block behind the intake manifold. The concept I'm trying to understand/visualize is supposedly when the oil pump is not in relief the oil pressure will be constant becuase the pump is flowing a fixed volume and all of it must go through the engine circuit... this is what the guys on BITOG.com are saying. They're saying that for restrictions to have an effect on oil pressure the pump must be in relief mode.
It very well could be that my HV oil pump makes over 52psi at the pump at idle (has a 52psi relief spring), and the pressure I'm seeing at the sensor is the drop resulting from traveling down the oil galley, through the filter, and up to the sensor.
It very well could be that my HV oil pump makes over 52psi at the pump at idle (has a 52psi relief spring), and the pressure I'm seeing at the sensor is the drop resulting from traveling down the oil galley, through the filter, and up to the sensor.
#30
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Re: Can hot weather cause lower oil pressure even when oil temp is the same?
I just re-read this... 1 degree hotter w/ the K&N filter should make the pressure even lower. It'd be different if I was taking a picture w/ the oil at 170 and saying, "see the pressure is higher" but I had it up to 215 and it still wouldn't drop below 49 psi.