What i was trying to say (im hopless at explaining myself in text sorry for confusing you) is that ruffly speaking basic suspension tuning on road cars like these from experience of playing on circuits and test tracks at manufacturers in my youth equated to a max speed increase in cornering speed of less than 10%.
I think that's being slightly unfair...it's entirely possible to achieve 10-15 MPH gains in corner speed, or 20% (speed depandant)...but as cars get better, and chassis more sorted from the factory, the relative gains get less.
Lots of factors to consider...and aiming for outright corner speed is always going to cost you elsewhere (braking stability, traction out of corners, wet weather ability etc)