The quest for speed and acceleration is central to automotive enthusiasm, and the 0-60 mph time is a key metric used to evaluate a car’s performance, especially for models like the BMW M3. When assessing figures like an M3 0-60, it’s crucial to understand the nuances of testing methodologies, particularly the concept of “rollout.” This term, while rooted in drag racing, often creates confusion when applied to standard 0-60 mph tests.
Rollout originates from the precise timing systems used in drag racing. The setup involves pre-stage and stage beams that cars navigate before launching. The pre-stage beam is simply a guide, helping drivers approach the starting line. Rollout, however, comes into play at the final staging beam. This is due to the slight distance—approximately 1 foot (actually 11.5 inches)—between where the front tire’s leading edge triggers the timing system as it enters the beam, and where the trailing edge exits, officially starting the clock.
A skilled drag racer using “shallow staging” can exploit this distance. By positioning the car just right, they can gain almost a foot of untimed acceleration before the clock begins. This effectively gives them a rolling start, adding a velocity of about 3-5 mph right off the line. This technique can shave off around 0.3 seconds from their elapsed time (ET) in a quarter-mile run.
The use of rollout is considered legitimate and even appropriate in quarter-mile drag racing. These tests aim to simulate optimal drag strip conditions that car owners might experience themselves. Furthermore, the National Hot Rod Association (NHRA) practices are followed for consistency, particularly in calculating trap speed at the quarter-mile finish line, which is measured as an average over the final 66 feet, not the instantaneous speed at the very end.
However, the application of rollout to 0-60 mph testing is a point of contention. Unlike quarter-mile runs, 0-60 mph acceleration is not a drag racing standard. More importantly, the very definition of a 0-60 mph test implies starting from a standstill – zero mph. Using rollout in this context essentially turns it into a 3-4 mph to 60 mph test.
While incorporating rollout might make 0-60 times appear quicker, shaving off around 0.3 seconds and potentially making cars like the M3 seem even faster, many argue that it misrepresents the true 0-60 acceleration. It can inflate performance figures and might be seen as misleading to consumers, even if it subtly enhances the perceived skill of the test driver.
Despite the temptation to use rollout to enhance 0-60 times, leading automotive authorities like Edmunds advocate against it for 0-60 testing. They champion publishing “real” 0-60 times, measured from a true zero start. To provide full transparency and shed light on this practice, they have started publishing both 0-60 times: one without rollout (the primary figure) and another “with rollout,” clearly marked for reader comparison. This allows consumers to understand the effect of rollout and discern the genuine acceleration capabilities of vehicles, ensuring fair and accurate comparisons when looking at metrics like the M3 0-60 time.
