I am glad somebody else bought this up. I have been mulling over thoughts on this subject for quite some time. I am not a proffessor in physics by any means but let me try to explain how i see it.
First off, unloading is a term that is widely used and often in the wrong context in relation to linked suspension and geometry. Like Rod said, the back plays into the front "unloading" period, on a steep climb or on flat ground... So lets break that term "unloading" down. When your front suspension unloads it is the springs decompressing because the whole weight of the front of the vehicle is no longer resting on the springs. This happens under acceleration and steep climbs from the back axle tranfering torque into the chasis and so on like earlier explained, and of course gravity. Now lets say you were able to do a wheely, the torque transfered to the ground from the rear end would cause the front end to come up and the springs would unload, now explain to me how the front link geometry has anything to do with that, even if you were in 4 wheel drive.
So after trying to make sense out of all that, now lets talk about forces exherted from the front end. Just like the back, when torque travels through the front axle and wants to turn the tires and transfers a counter torque through the front links and into the chasis this would be anti-dive. Depending on how much anti-dive you have from your link geometry the front AXLE will either be PUSHED DOWN or PULLED UP to the body from the torque. (notice the choice of words.) Just over 100% anti-dive would mean the front axle PUSHES the body up away from the ground which means the axle itself is being pushed TOWARDS the ground. MEANING MORE TRACTION. Yes the springs will decompress a little which seems like they are "unloading" but I dont see it that way. And yes, too high of numbers over 100% anti-dive can cause problems like the springs completely "unloading" and falling out.
That said, the main reason I wanted to write this is because everyone kept on saying that certain setups cause the front end to just "unload" without any explanation when there is alot more to it than that. The whole front end isnt unloading, the geometry of the links are putting forces on the front end causing the body and axle to push apart from each other and leave the spring in the middle without as much pressure on it.
Im sorry if my thought process was really confusing but alot goes on in my head at once. lol
Like I said, just my thoughts on the whole thing and how it makes sense to me in my head.:lecture:
Now tell me im crazy.. :looney: