I used the corolla rally car. It was up to 444hp.
I set the power to 50/50 front/rear, its normally 30/70. TCS is off, ABS 1 or 2. ASM off.
The key is to be quick through the turns obviously, sliding is not the answer. I have gas and brake on R2/L2 to make it easy to use them at the same time, heavy braking but not late breaking, early on the gas while still finishing braking and take tight tidy lines through the corners.
I actually did the gravel one with the car at 360hp and won by half a second after i botched my 11 second lead on the final stage with a spin. The extra horse power will likely make the straights good places to gain time.