This article is a nice reminder that picking parts based purely on highest horsepower number doesn’t always produce a faster car. The author took the example of a tall, long runner EFI intake manifold versus a production LS1 intake. With the long runner manifold, the engine did produce more horsepower but it moved the torque peak off the middle of the curve, resulting in a slower simulated quarter-mile run.
The article below can best be summed up with this quote
my buddy Lingenfelter told me the best engine modifications to make a car quicker were mods that would improve the power within the rpm where the engine spent most of its time.
Source: On All Cylinders