Your question is a little vague, but I will do my best to address it. A "racer" prefers whatever will make him/ her more competitive. As for which is faster? As far as the time it takes to shift gears, no human wil consistently outshift an automatic/DSG. As far as which is faster, or, quicker? It depends on the application. In road racing for instance the manual is lighter, easy to setup, and uses less horsepower in transition to the wheels. It also has fewer moving parts, (lesser chance of breaking). Reliability starts becoming more of an issue when power levels climb towards, and past 1000 hp,( which is rarely seen in roadracing, but has been done). Traditional automatics are used extensively in drag racing due to consistent shift times, and their ability to withstand tremendous horsepower when properly set up,( the GM powerglide has been used at power levels exceeding 2000 hp). I think what you may be referring to are acceleration times between new generation automatics vs. manuals, and in many cases the auto is quicker but the explanation is simple. If both cars, (manual & auto), have the same engine, and the same final drive gear ratio, but the manual has 6 speeds, and the auto has 8 speeds, the auto will probably be quicker for 2 reasons. (1) the auto will shift gears faster than the person driving the manual, and (2) due to the closer spacing of more lower gears the engine will stay in its optimum power range longer, (it wil go thru those gears quicker), hence, the automatic is "faster". The technology exists today to make either transmission as good as the other. It simply comes down to how much you want to spend, or what you prefer.
