The game's horrendous wheel spin modeling means you will almost always
lose positions off of the start, no matter how well you feather the
throttle. To minimize this, don't let the revs exceed 10,000 RPM when
the red lights go out, and don't feed on full power until your speed is
more than 60 miles per hour.
On a similar note, do not apply any gas whatsoever after you spin or slide
off the track. You can turn perpetual doughnuts in sixth gear with a half
ounce of throttle pressure (even while still on the pavement), so you must
be patient and get the car rolling by using only idle-level RPMs.
Select the softer compound tires (D2 for dry weather, W3 for wet weather)
for all races. The wear factor is so minimal that, even in a full-distance
race, the tires will probably last at least until the halfway mark.
Although the garage menu offers some user-friendly car adjustments to
experiment with, you don't always need to use it. At many of the tracks,
you can generally snatch pole position with the default setups.