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All right, I know I need an EGT gauge, but I can't decide between an oil temp and an oil pressure gauge. I spent the whole afternoon at work trying to research it by searching here and NASIOC, but I couldn't find any definitive answers. If you had to choose between the two, which would you get?

While I think they look cool, I don't think I want 3 60mm gauges on my A-Pillar, which is why I'm trying to decide between these 2 for my 2nd gauge...but I do know which gauges I want to get. The gauges I want don't come in 52mm, so that's just the way it's gotta be :)

(and no, like my wheel choice, only a select few know what gauges I'm gonna get...heheh)
 

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I think ive come to this decision once before. I believe I settled with the Oil Temp. I think it'll give you a more accurate reading of when you can "get on it" and when you can "turn it off" *unless you have a TT*

Oil pressure may be useless...because is something goes wrong there, you are going to know it on every single other gauge. I can see how it would help if you suddenly broke a line or something, but It just seems to me that the temp would be more useful.

Hope this helps a bit :)
 

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I always use oil temp. I think monitoring the temperature is good to let you know how hot things are running and how lopng to let it run before getting on it. The oil pressure doesn't tell you anything unless you've lost pressure which I've never had happen. If you lose a lot of oil pressure your oil temps will instantly skyrocket as well.
 

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idiot light

i believe that the wrx has an idiot light if you loose oil pressure, so in a round about way we have the most important feature of an oil gauge. i have an oil temp for the same reasons already mentioned.
 

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I would recommend an oil-pressure guage. Especially if you already have EGT guage, then the temperature factor for safety can be monitored there.

The pressure guage is nice because you can sometimes see if you are leaking oil or getting low. You would also be able to tell if you were cornering hard, and getting oil starvation. Last but not least, it will tell you when you NEED an oil change.

My 3000GT had an oil pressure guage and it would start to read lower and lower right around 3000miles on the oil filter. I could actually SEE when the filter was getting too dirty and needed a change. I'd change the filter, and presto, full oil pressure again.

-Jason
 

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I have both an oil temp and oil pressure gauge. Unfortunately i have never noticed any difference with the oil pressure gauge when the car is a quart low. It would be nice to have some kind of gauge to tell you instead of having to read that stupid dipstick.

The only thing i notice is the oil pressure is high when the engine is cold and idling. When the car has warmed up, the oil pressure begins to drop. The oil temperature gauge can be used for the same thing.
 

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I am going to say get the temp gauge instead of pressure, like everyone else says, there is a dummy light, and pressure doesn't fluctuate quite as much as temp does.
 

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RallySubie said:
The only thing i notice is the oil pressure is high when the engine is cold and idling. When the car has warmed up, the oil pressure begins to drop. The oil temperature gauge can be used for the same thing.
This is most likely due to the fact that (as we all know) colder oil requires more pressure to move it and as it warms up it flows better (read more easily) thus requiring less pressure. Of course synthetic oils are much less prone to this.

I agree with the oil temp guage over the oil pressure guage any day. I'd think that the temp change would be more efficient way of monitoring what's going on...
 

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Shard said:
I am going to say get the temp gauge instead of pressure, like everyone else says, there is a dummy light, and pressure doesn't fluctuate quite as much as temp does.
Well....... I have a temp gauge, and it is helpful a lot....... however, from what I've read, the dummy light doesn't come on till like 2.x PSI, which is REALLY low. And you've already done damage if you're on the gas with that pressure.

Uhhhh, if I had to choose........ I'd chooose both! haha, not much help...... but you should have both....... oil is the life blood of your engine.

Blue
 

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I got the oil pressure gauge. For the engine temp, I just look at the stock temp gauge. I also have an EGT.

If you ever decide on getting the oil temp, dont ever get a manual gauge. I had oil all over my dash board bcoz of that.( hose leak ). Get an electronic gauge.

The temp gauge tells you when your engine is really warm. Also you get an idea about the viscosity of the oil with temp.
 

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Osiris said:
IOil pressure may be useless...because is something goes wrong there, you are going to know it on every single other gauge.
It isn't useless at all. I'd go with oil pressure 100%.

The two gauges usually serve two functions. The oil temp(OT), is like water temp (a real gauge) in that it shows you what ready-state your motor is in (ie warmed up, over heated, too cold). This is good for daily motoring.

The oil pressure(OP) is like an EGT in my mind, in that it's a "if shiz happens, I'll show it." Monitoring OP can be very useful. I've used it on past cars and you can tell if your oil pump is being lazy (over time), when the car is fully warmed up (it'll lower to normal pressure when it is fully warm), and more importantly if you lose oil pressure or aren't holding enough pressure. If you're at WOT and the OP starts to go down, you KNOW to get off of it.

I've swapped oil pumps before and the 2nd pump consistantly was 15-20psi lower at high rpms than the other. This wouldn't nec be clear from seeing oil temp alone.

The OP and OT show similar things, but sometimes it's hard to tell from OT what is happening. Your oil temp can rise because of abuse or insufficient oil cooling, but that doesn't mean you lost an oil line.

Again, not knocking OT, but my preference is OP.
 

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I say oil pressure is more important.

Oil warming up...you got time...

Losing oil...shut down NOW!
You can never get this info fast enough, and if you wait until the dummy light lights up...it's possibly too late already...$$$ bye-bye.

That's my opinion. Comparing the two, I rather have warmer oil than no oil.

Still...my plan is to get both plus EGTs on the pillar and a boost on the column.
 

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I'll get the pressure guage over temperature guage

the stock dummy guage is simply on and off switch to the ground

it will only turn on above some pressure and shut off below the set pressure..(on/off)
I doesn't really tell you if your pump is going bad..

the real guage make you sure that your oil pump and pressure relief valve is working normal condition.. it also tells you if you have good positive crank vanltilation system and good crankshaft main bearing etc..
 
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