Brock Yates - the originator of the Cannonball Baker Sea-to-Shining-Sea memorial trophy dash has a really good book out about all the races with storys by some of the greats including dan gurney. I remember reading an articel he wrote about it years ago saying the best car for that race was an american muscle car (he won it one year in a 1971 challenger) because it was innoccous enough, carried more fuel than the exotics, and was comfortable.