Coming from a RWD prone to oversteer, I totally feel ya when you say that the legacy understeers!
Front braces / sway bars or anything like that will likely increase understeer so I would avoid those.
+1 to what @JGM said, good sum up.
I went with :
- Whiteline adjustable RSB (20mm) on the stiff setting
- Ultra racing lower brace
- Sachs shock absorbers
The RSB makes a massive difference in the middle of the corner and corner exit (allows you to put some more power without understeer). It won't fix the understeer if you enter a corner too fast though. If your suspensions are shot it's worth changing them as well. In my case it was night and day between the Sachs and the 150 000 km stock suspensions.
I installed the Ultra racing lower brace after installing the RSB and I don't think it makes a noticeable difference. The reason I bought it was to reinforce the sway bar mounts. My sway bar mounts were actually slightly bent when I installed the lower brace so I reckon it's a good purchase.
The way my car is currently setup, I reckon I have a good balance for performance applications. When cornering at the grip limit, at half throttle :
- If I accelerate more, I get understeer
- If I release the throttle, I get oversteer
Which makes it really easy to keep the racing line you want.
Except if you like driving at the limit or drifting, this way you can do it at slower speeds
(I have shitty tyres and don't mind it)
I recommend you try the Michelin PS4 bro.
I had the PS3 on 2 cars and they are similar to the RE003, just a little better on the rain. The PS4 are a good notch above in every domain.
And they also last longer than both the RE003 and the PS3, which makes good value for the money.
When I'm done with my shitty tyres I reckon I'll get these.