So this isn't motorsports but I figured it's close enough to go in this subforum

Here are my best laps from my last two outings, August 15 and September 19 this year. P.S. How do I embed youtube videos???
August 15 - 1:29 (just)
https://youtu.be/4sBZEqy9dZE
September 19 - 1:27
https://youtu.be/ZOxFclOEqdA
I know I should brake later and can definitely carry more speed through corners, but with Sandown I get the impression that you don't want to find the limits of your brakes, tyres of ability there!
What sorts of speeds should I aim for on each corner? When do people generally brake? I'm currently targeting 40psi tyre pressure when warm, is this too high/low?
For the sake of completeness my WRX has brembos, decent rotors/pads, a 6 speed box, around 230kw and i'm running 225 wide Yoko AD07 rubber.
Thanks in advance, I know the WRX club has a wealth of experience so any tips would be gratefully received and appreciated

Mike