I have searched around, and I've found various psi for my size. (from like 35-50).

I am running 235/40/18 on Ventus (all seasons) on 18"x8.5" wheels.
Max Psi on that tire is 50psi. Car is 03 WRX.

I live in Vancouver (around 23-27degress C in summer).

I just want daily driving, no autoX what so ever. (there are some pot holes in my area, so I don't want to over inflate).

I am currently running 40psi front and 38psi rear. How's that sound?

any advice? who else is running on those sizes ????

THX !!
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sounds high..
I'm running cold tire pressure about 35psi front and 31 psi rear on my Falken Azenis RT-615's using same size tire/rims as you.
Hows your tire wear? is the middle wearing before the outsides? If yes, pressure is too high.
When I start running over 35 in front, grip/turn in suffers.
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Ride seemed to be a little bit firm. Feeling a lot of bumps on road.

I dropped it to 36Psi Front and 35Psi Rear.

in the heated afternoon, it goes up to 38,36 respectively.

That sounds better ?!
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