[About the oil pressure]
I mounted the camera in this position to monitor the oil pressure change on the track. I found that the pressure was consistently around 60 PSI during a lap when the oil temperature was around 210F. However, at T5 (the esses, right hander following the T4 left hander) and T8 (the hilltop), the oil pressure would drop to 20~30 PSI for a brief moment. Keep in mind that I have and external oil cooler installed and use 5w-30 engine oil.

My friend with a similar setup on his GR86 observed the same pattern by looking at his logged oil pressure data.

[About the lap]
The weather was great in the morning but I was not able to put together a great lap to be on the podium this time. This 1:28.8 lap only got me P4. The competition is very fierce and everybody was driving so well!

The first half of this lap is good but I struggled to rotate the car in the two hairpins (T7 and T10) which caused a 0.5~1 seconds loss from the data. I did better hairpins in the later laps but the overall grip dropped as the tires got hotter so I did not improve my lap time. 

TH west is really a track that demands high precision driving in every corner to get a good lap time. Still need to improve my consistency of execution, especially braking.