you look to bulky to sprinting.
Ben Johnson. 
I felt good at that size, I even thought I need to get bigger.
How bout that white boy from greece who won the 200m in 2000. Then he bailed out in 04 because he was probably using something illegal. Still… that is one speedy non-african.
i dont think kostas kenteris has ever done an official sub 10 time. Cant be sure though
sad case, they crusified him and his teamate katerina thanou…
though the track comitee here in greece deemed the athletes inocent and gave their coatch (tzekos) a four year ban…
Although a lot more info has come out in terms of training methods, in jess javers book sprints and relays there are a couple of articles written by old soviet coaches that touch base on the topic of genetics and finding sprinters. Some quotes that caught my eye are… " It is known that sprinting ability (cns, distribution of muscle fibers, neuromuscular coordination, tolerance of oxygen debt, ect) depends far more on genetic factors than training methods. It is also known that of all physical performance components, speed is the hardest to develop…successful development of sprinters depends to a large extent on their inherited talent. Talent identification is therefore the most important factor."(Torim) Then in another article by Tabatschnik it says that " An analysis of the performances of the world’s best sprinters shows that all began with fast times. The average 100-meter time for the first performances of the group analyzed was 11.34 and consequently the improvement rate was extremely limited, ranging only from 0.98 to 1.64 seconds (8.5-13.3%). Such limited rate of improvement stresses the need for careful identification of potential world-class performers in sprinting. Analyses of anhropometric measurements indicate that height, weight, length of limbs ect., have little or no correlation with performances. As there is still noclearcut understanding of the physiological mechanisms of the speed-deciding abilities, it appears essential to base the identification of sprint potential on parameters of an ideal “model.” "
I am not sure if these ideas still hold weight they were written some time ago but Jess Jarver seems to have a lot of informative info on track and field. The soviets seemed to have written a lot of stuff about how they looked for certain things in children, then sent them to specialized schools to develop this talent.