Did not want to hijack Rob7's build log, so I thought we could move the discussion to here. Chuck was kind enough to post this calculator, so I decided to play around a bit to get this straight in my head.
The numbers that I came up with are about 1,300 lbs force on the upper link and 2,100 on the lower. What isn't quite clear from the calculator, if this is per side, or for both sides. My guess is that it is for both sides. As I understand it, the upper and lower link forces are acting in opposite directions, with the difference being the force that propels or retards the car. Under acceleration the lower link is in compression and under braking in tension. As the tire rotates around the contact patch, the upper link works on a longer lever, thus having to exert less force.
What I take away from the whole exercise, is that the forces are not overly great. But maybe I'm missing something, so please chime in.
http://mysite.verizon.net/triaged/4link ... index.html