It's just as silly as the forum has been around for 4 years, but the same questions are still being repeated asked instead of searched...
Big things:
Oil Cooler, if you have a 12 you have a very basic cooler which would suffice for your first few runs until you really push it. Then you're going to want to look at upgrading.
Brakes will suffice for your first runs, again as you become more skilled and push harder, the important parts are the Pads and Fluid. Upgrade those and you will be alright.
Fuel starvation is mostly solved by making sure to fill up after every run.
Everything other then that is specific to your situation and concerns/ability.
