Fully tune it to around 1000Bhp, use the hardest tyres and don't pit. Alternativley youcould win the endurance race (I can't remeber which one but you can find out in the FAQ) that gives you the Zonda race car and win it then.
The Key to winning this race, is driving the car. What that means is hit the brakes twice as early as you think you need to, Ease the throttle back on, and take it nice and smooth through the turns.
In race one, the AI pit on lap 9, on Race two, the AI don't pit. Take it easy and smooth. DOn't get yourself flustered, as that will cause you to over react in accelerating and turning.
Hi Zonda_fan & Welcome to the GTP Forums: 👍 The "Short Answer" is: You DO NOT NEED 1000 hp to win these races. Everyone in an OLR group I race with was able to win with the mods listed below. PM me for chassis settings if you need them...UB57
The right combination of parts on the C12S brings it right up to speed with the race car.
Equip your C12S with the following:
full race suspension
sports brakes
brake balance controller
stage 1 tune-up
full engine balancing
sports chip
full race transmission
triple clutch
race flywheel
full LSD
medium-slick tires (T4)
lightweight 1 (giving you an 88 kg advantage over the racers)
When fully run in, the car will have 682 hp.