I'm thinking of upgrading springs on my car. Here is what I have:
2011 MX-5 soft top with sport package
Racing Beat sway bars, front and rear
Currently run 215/45 r17 on stock wheels (plan to switch to 245/40 with 17x9 wheels)
I do autocross the car and want to make it a bit more competitive and fun, but at the same time it's my daily driver so nothing crazy (60 miles a day

I'll also install FCM bumstops, but what length and stiffness should I use?
Appreciate any help!