Using the same rates on every car isn't gonna work as well as it did in GT5 unless they're all very similiar weight/wheelbase. Suspension seems to have a much larger effect than it did in GT5.
9/7 is probably perfect and close to what I would use for a car hanging around the 1200-1250kg (2600-2750lbs?) area.
Although, on my 1450kg(3200lbs) Chaser I run 18/12, and it's a considerably longer wheelbase than the lighter cars I have, so you can sort of see the pattern.
--
OT: 80%+ of the time normal mode, unless friends are in a DT.
I don't know... I just find it strange when everybody has extra lock, it's not like everybody at a drift event in real life is gonna have a wisefab kit. I just want to drift, I don't need an aid to let me get HELLA ANGLE YO.
Also, albeit I'm on DS3, but I don't notice a difference in physics, it just feels like back in the GT5 hybrid days when you edited your steering lock in hex. I neither see a reason for them to change the physics in DT mode, I'm 100% sure it's the same just with extra lock.