Every article by race engineer, Jeff Braun, is valuable, and this week's is no different. Jeff writes about differentials - their purpose, the different types, and what you as a driver can do with them. Adjusting and using your mirrors properly - on the street and on the track - is the focus on this week's Speed Secret. Ross also writes about the legendary Carroll Smith - what he wrote (that you should read), as well as sharing a couple of stories about him.
