I don't do much straight line racing or testing, but I may be able to get you pointed in the right direction. To start with, you're going to want the car low, as low as it will go. This reduces the frontal area of the car, and also reduces airflow under the car. You'll also want as little camber as you can get away with on the driven wheels, and none on the undriven wheels. This reduces the formation of drag inducing vortices between the rolling tire and the stationary road, and also puts as much rubber as possible on the road in order to put the power down in initial acceleration. As for engine and transmission settings, those are far more dependent on the car, but a high revving engine will want higher gear ratios so it is in the powerband as much as possible. Conversely, engines with more low end torque will not benefit from high gear ratios since the power is lower in the rev range.