88kPa vs 108kPa radiator cap, coolant temp

[OilStained]

Hey B’ers,

I have a Toyota Sienna hybrid and have a ScanGauge connected to view the coolant temp. I have both an 88kPa and 108kPa radiator cap.
With the 88kPa cap, the max temp reaches 200F. With the 108kPa cap, the max temp reaches 190F.
What are some reasons I should use one or the other? Such as efficiency running hotter or cooler.

 

[Chris142]

A cap has no effect on coolant temp. It only raises the boiling point.

 

[Rand]

So those are 12.x and 15.x psi caps

Pressure raises the boiling point of the coolant has no other affect.

 

[OilStained]

I’m observing a diff of about 10degrees between the 2.

Which one is preferred, running at a lower or higher temp?

 

[Rand]

I’m observing a diff of about 10degrees between the 2.

Which one is preferred, running at a lower or higher temp?

Are you observing the sun rising in the west too? That makes about as much sense.
Caps have nothing to do with the temperature of the coolant.
I'd run an OE cap with the stock pressure.

It's like asking if your phone should be louder in the sunshine or the shade.

 

[OilStained]

Are you observing the sun rising in the west too? That makes about as much sense.
Caps have nothing to do with the temperature of the coolant.
I'd run an OE cap with the stock pressure.

It's like asking if your phone should be louder in the sunshine or the shade.

The sun sets in the East, what’s your point. ATQ. If you don’t have an answer, not looking for an argument

 

[CleanSump]

The answer is; The pressure rating of the cap has no affect on the temperature of the coolant. Totally irrelevant.

 

[OilStained]

I know what I see on my SG2.

Then let’s take the kPa out of the equation. If my normal operating coolant temperature is at 200F, and I can do something to make the coolant temp drop by 5 degrees to 195F, should I do that or not?

Maybe depending on my application, daily driving.

Maybe 5 degrees is not significant, then how about a 10 degree drop to 190F.

Or running 200F is the better? For long distance tripping?

 

[Boomer]

Personally, I would run the hotter of the two. Helps keep the oil a bit hotter to burn off condensation and fuel from short tripping.