i searched John Dees forum to make sure this hasn't been posted before. i couldn't find it. anyway, check this thread out. notice this guys number of posts and what not. seems all very legit to me, as a matter of fact i have been doing this in all my cars for a few months now....with great results! please post your opinions! thanks!
http://www.ls1.com/forums/showthread.php?t=91206
http://www.ls1.com/forums/showthread.php?t=91206