It's all about high g forces with heavy throttle input. A lot of people run drag radials on the street. If you launch the car hard and you a pinned back in the seat hard the trans fluid is also thrown to the rear. Hard old style street tires won't do it so no problem there haha.
Yeah, and it might not even be that. These discussions have gone around in circles for years because everybody's speculating. I've been lucky enough to actually instrument my car. Here's my fastest autocross run from the 2019 Bristol National Tour event:
Green line is transmission line pressure. Now, some of you experienced folks will see these pressures are low. This trans was hurt badly, it came out for an overhaul right after this event and the nylon stator support bushing had melted out of the pump. Oops.
BUT! It still worked, and this chart still can tell us if I uncovered the pickup:
The first arrow is pointing to the line pressure during a long sweeper. The car was pulling 1.2-1.5 G laterally for almost two seconds. Transmission line pressure dropped to ~25-30psi (left side arrow).
But it settled at the same pressure after the run when I was at idle (right arrow).
So even during a long sweeper on super sticky tires pulling 1.2-1.5g, I didn't uncover the pickup and suck air. Same pressure as sitting level at idle in the pits.
This is a deep pan with a 700-R4 filter filled half a quart past full on the dipstick. So, go with a bottom feed filter for a street car. Anything more is just bling. If you want a fancy nice pan, that's up to you. But you don't need it.
If you're pulling 1.3 60' times and packing the front wheels past the lights, well, you're not exactly a mild street car on Radial TAs anymore, are you? Different discussion.