This weeks episode of CarCast with Adam Carolla and the Professor Sandy Ganz brings Harold Osmer. Harold is the Author of "Where they Raced" a detailed book on Southern California racing from 1900 to 2000. We toss in a special old recording of Adam's version of the hyper-amped Drag racing radio promo you might hear back in the 1980's. Another Tech segment? Yes, the Professor experiments with air filters and finds out that they can be renewed and which flows the best. Pictures and video at www.adamcarolla.com/CarCastBlog Enjoy the show!