GR Yaris GR Yaris and oil pressure (in track use)

Michael Knight said:
How does oil pump perform with thick oil? Must work 2x due to higher viscosity
Click to expand...
Probably not an issue though I don't have data for the various oils being discussed but a quick look suggests:

0W at 40C has a kinematic viscosity of 45 mm2/s
5W at 40C has a kinematic viscosity of 46 mm2/s
20W at 100C has a kinetic viscosity of 8.54 mm2/s and
50W at 100C has a kinematic viscosity of 17.7 mm2/s

There isn't much data available because this is all secret squirrel and obviously doesn't cover the range of temps the cars see in real life but it is all I could find from a couple of manufacturers like Castrol and Nulon.

That suggests that while the 50W is thicker at 100C as you would expect it is still much thinner than either the 0W or 5W cold. Thus the galleries and pump should have no issue. Again based only on the data that I could glean in a 6 second google...
 
Last event have some unstable oil pressure at brake and turn ( oil is 2 track day old)
Change new oil and put extra 500cc into engine , so far no issue of oil psi

IMG_2746.webp
 
Started logging oil pressure during my last track day...
Not too good:
usually it did not go below 1.3-1.7, but had 2 instances of 1.1bar 🤔

Stock car, -3°/-2.7° camber, continental spc7 225/45 R18 (tyre shop mixed up)
+0.4l overfill
Track is pretty sticky - measured 1.3-1.4g

Here I did provoke the car (short hard brake during cornering), but no wide semis 🤔🥺
Screenshot_2024-01-06-18-43-38-50_0085a1dbb73ac86b64dde297b817c1d7.jpg


Here's a video of a few laps:
 
Orion said:
Started logging oil pressure during my last track day...
Not too good:
usually it did not go below 1.3-1.7, but had 2 instances of 1.1bar 🤔

Stock car, -3°/-2.7° camber, continental spc7 225/45 R18 (tyre shop mixed up)
+0.4l overfill
Track is pretty sticky - measured 1.3-1.4g

Here I did provoke the car (short hard brake during cornering), but no wide semis 🤔🥺
View attachment 23463

Here's a video of a few laps:
Click to expand...

looks like you were pushing quite hard. I'd recommend getting the baffles installed. In addition keeping the oil temp low enough helps with keeping the pressure sufficient. this is the strategy I've chosen, and prefer it than getting into trouble and discussing with Toyota if warranty fixes everything. But understand both approaches.
 
those who have that oil pressure data it might be interesting to hear the official statement from Toyota if those drops of PSI are ok or not.
I think it would be hard for them to agree that they will not cause any concern as the min pressure recommendation was 2bar for engine in the manual.
 
Michael Knight said:
those who have that oil pressure data it might be interesting to hear the official statement from Toyota if those drops of PSI are ok or not.
I think it would be hard for them to agree that they will not cause any concern as the min pressure recommendation was 2bar for engine in the manual.
Click to expand...
I intend to discuss this during my 50.000km inspection, due in a few weeks
 
Michael Knight said:
looks like you were pushing quite hard. I'd recommend getting the baffles installed. In addition keeping the oil temp low enough helps with keeping the pressure sufficient. this is the strategy I've chosen, and prefer it than getting into trouble and discussing with Toyota if warranty fixes everything. But understand both approaches.
Click to expand...
The key takeaway for me -- it IS quite possible to reproduce a significant oil drop even on OEM size street tyres (actually I am quite sure 225/40R18 would be even more direct/stickier than my 225/45R18)

Apparently you can minimize this by smoothing your inputs (I only got a noticable drop when I slammed on brakes or did an abrupt streering input) but yeah, this has to be dealt with
 
Orion said:
Started logging oil pressure during my last track day...
Not too good:
usually it did not go below 1.3-1.7, but had 2 instances of 1.1bar 🤔

Stock car, -3°/-2.7° camber, continental spc7 225/45 R18 (tyre shop mixed up)
+0.4l overfill
Track is pretty sticky - measured 1.3-1.4g

Here I did provoke the car (short hard brake during cornering), but no wide semis 🤔🥺
View attachment 23463

Here's a video of a few laps:
Click to expand...

Try to add additional .5QT
To see if this improves
 
I've managed to reproduce an oil pressure issue on a public road with standard size winter tyres 😨

Stock car, 0.5 liter overfill, changed every 5k km

Just slammed on the brakes really fast at around 100km/h in 3rd gear for 1-2 seconds

I agree its not a typical use case, but I'm starting to worry...

Screenshot_2024-01-14-17-52-15-16_b9c66f921be6b9ee18febc2ed6906538~2.jpg
 
I think an extra 0,5 litre will help prevent that
 
Duke said:
I think an extra 0,5 litre will help prevent that
Click to expand...
at least on track it is not sufficient especially with hot oil. tested last summer. My oil gauge went all south in hard braking and thus decided its not safe to track the car without baffles. Everyone has of course own limits but I prefer to run it on safe side. Much more fun to drive as you dont' constantly need to keep on looking at oil pressure gauge.
 
Last edited:
You must log in or register to reply here.
Back
Top