As far as mods a power steering cooler and even an underdrive pulley are a must in my book. I should know because I fried to power steering pumps in one day at the track. Stock brakes do OK at Willow but some tracks are much harder on brakes then others. For instance at Las Vegas Motor Speedway my Power Slot rotors and PF pads got so hot they were somoking and my ABS light came on and the pedal would go to the floor and have little stopping power. If you are running stock brakes I would flush the sytem before every event and put some fluid in with a high wet/dry boiling point. I also think racing harnesses help a lot. They really reduce fatigue and can actually improve your lap times, while also providing more safety.
Lets keep this going and see what others think.
Lets keep this going and see what others think.