magic wheel fitment

few questions (s14 application but any info is helpful)

this is on the front btw (also this is regarding wheel fitment for drifting / racing, im all about hot wheel fitment but i have to maintain some degree of function)

how much clearance is needed between the top of the tire and the upper fender rail before you eat shit on it every corner? 2 inches? more? less? this is with KTS coils, 8k front spring 

secondly, has anyone figured out the sunk-to-tuck ratio? haha. obviously if your front wheels are sunk, you can go mad low in the front without rubbing, and if they are super flush, you can only tuck like 1cm of tire. anybody know the happy medium? like how sunk would i need to go to tuck half of a stretched 235/40? 2cm clearance between fender and tire? more/less?

any ballpark guesses would be helpful just seeing if anyone knows before i just go trial and error it.

mercer it would just call for more camber. Not ol' school demon camber, but a bit. Then you can still have aggressive fitment and clearance. Otherwise you'll have Chewbacca fitment.

I thought you had flares on the front? 

yeah i had 265/35 on the front, on 18x10 -7, but i got 235/40 on there now so i have a lot more room to work with, and want to take advantage of it haha. im running ~3 degrees camber. i either want to take out half a degree of camber or lower it and keep the camber at 3, i guess i just need to mess with it.