Oil pressure on a /6 under load Options

[SirAndy]

What is the max oil pressure i should be comfortable with (under load) on my 3.6L?

I've been reading 993 manuals and posts all over the tinterwebs and all i can say for certain is that the stock 993 gauge seems to max out at 5 bar but according to all the info i found you'll get there already around 3k rpm and then the gauge just sits at max.

The reason i'm asking is that i'm using a gauge showing psi instead of bar (with the correct sender for that) and 5 bar should be around 73 psi but my oil pressure is substantially above that under load.

I'll idle around 40 psi (sometimes drops to 25-30 when it's really hot) and hit 100 psi as soon as i get above 3k rpm and pretty much stays there.
I've seen as much as 110 psi.

100 psi is about 6.9 bar
110 psi is about 7.6 bar


Question is, am i about to blow up my engine running these kinds of pressures?
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[Mark Henry]

IIRC there is a oil pressure relief somewhere on the 3.6, I'd check it's operation.
Do the mechanical gauge temporary taped to the rear window so you can see it in the RVM trick, I've done it a few times for fuel pressure issues, works well.

[SirAndy]

IIRC there is a oil pressure relief somewhere on the 3.6, I'd check it's operation.
Do the mechanical gauge temporary taped to the rear window so you can see it in the RVM trick, I've done it a few times for fuel pressure issues, works well.

I know of the pressure relief valve, which is a contender.


Stupid question, could a clogged up oil filter cause this?
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[porschetub]

IIRC there is a oil pressure relief somewhere on the 3.6, I'd check it's operation.
Do the mechanical gauge temporary taped to the rear window so you can see it in the RVM trick, I've done it a few times for fuel pressure issues, works well.

I know of the pressure relief valve, which is a contender.


Stupid question, could a clogged up oil filter cause this?
(IMG:style_emoticons/default/idea.gif)

Not a stupid question really,I don't think so because you should have over pressure valves in your filter housings,or atleast I know there's one in the tank filter housing on my car...spring and ball on a round seat.
Even if your system is different the filters themselves should have in built reliefs but I don't know @ what pressure they bypass.

[Mark Henry]

IIRC there is a oil pressure relief somewhere on the 3.6, I'd check it's operation.
Do the mechanical gauge temporary taped to the rear window so you can see it in the RVM trick, I've done it a few times for fuel pressure issues, works well.

I know of the pressure relief valve, which is a contender.


Stupid question, could a clogged up oil filter cause this?
(IMG:style_emoticons/default/idea.gif)

Not a stupid question really,I don't think so because you should have over pressure valves in your filter housings,or atleast I know there's one in the tank filter housing on my car...spring and ball on a round seat.
Even if your system is different the filters themselves should have in built reliefs but I don't know @ what pressure they bypass.

They don't really bypass at high pressure, they bypass at a differential in pressure of the in/out sides. It's not a big number maybe 10 psi difference. What controls the pressure in the circuit is the engines pressure relief valve(s).
If it's not the sensor I'd do a full oil change, cut open the filters, check the sump and check the operation of the pressure relief valve...
I'd still hook up or T in a mechanical pressure gauge first.