If you were to make a car (A V6 Alfa 156) into a track day car, with coilovers, antiroll bars and the lot, and you put semi slicks onto it (like Toyo R888 or Federal RSR 595) tires onto it, would you regret it very fast?
I have been track-daying with my 156 3.0 V6 SW and been building it up slowly - 1st off you have to stay safe - thus work the brakes 1st (but don't go overboard). Most important PROPPER
brake pads - I have killed a set of Messi brand pads in 1 day (I got desperate while my EBC's were on order). I ran EBC Yellow stuff with good result - I would recommend - I am currently on Endless track/street pads. Then propper brake fluid - I run Endless S-Four
The Brake pad upgrade and Semi-slick tires brought me down from 1:27 Lap time around Zwartkops to 1:22 (where fast full race-trimmed weight-reduced road cars (Trofeo-class) do 1:15)
I installed a Q2 diff and that brought me down to mid 1:20's
I installed D2-racing shocks (firm street spec) and that brought me down to low 1:19's
I have now installed Eibach Anti-Roll-Bars and front strut brace, but have not been around the track yet.
Back to the real question: OIL mods - as said - not needed. I have had a water bottle crack on me at a track day - after letting it cool down I managed to get enough water back in to drive the 6km back home. Over-all the car survives quite OK mechanically - just be sure your fluid levels are fine - regularly (between sessions).
Oh and lastly on tire life - it is not that bad if you don't COMPLETELY
abuse them. I get about 8 track days out a set. The biggest tire killer is overheating them - they blister off - DO NOT
run too low pressure - I killed a set of front tires at 1.7bar - at 2.4bar the new set survives quite OK.