This happens both up/down at 8bps. If you lower maxSpeed to 1 the cart will now properly stop when going down, but will still clip through block when going upwards.
Reproduction Steps
Build this setup
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Send a minecart up/down
Observed results
The minecart continues to move despite that it's hitbox should have colided with the blocks above the track.
[media][media][media]
Expected Result
The minecart would be stopped by the block
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(Like it does at 1bps when going down)
Can confirm:
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