So, this FC contraption with a stock sway bar, I wonder how much articulation would be lost even with the weakest spring combo? And how much stability off road would it provide vs. AR?
Wouldn't a torsion bar be progressive? The more you twist it the harder if fights back, right?
Yes, but not exponentially harder. That is why progressive is a little difficult to understand. The further I push a linear spring, the more it pushed back against me, right? A lot of people will say that is progressive, but its not. Its linear. Let me try to explain the difference:
Lets say I have a compression spring that has a rate of 100 lbs per inch. Now, to compress that spring one inch, it takes a force of 100 lbs, Right? Force (F) equals Spring rate (k) x Displacement (D)
Now...If I compress that same spring two inches, what is the force required? 200 pounds. And...since Every action has an equal and opposite reaction, that spring is pushing back against me with 200 lbs of force too. Now, to go to 3" of compression, I have to add another 100 lbs of force. Notice that no matter where I "start" to compress the spring, each inch of compression requires a 100 lbs of force.
So, that is a typical linear spring. If you make a graph of the force required to compress the spring "x" distance, the graph will be a straight line.
A progressive rate spring, on the other hand, will require different amounts of force to compress it an inch, depending on where it is in its travel.
Its spring rate may be 100 lbs per inch on the first inch of travel, 200 lbs per inch during the second inch of travel, etc. If I have a spring compressed to one inch with 100 lbs of force then apply another 100 lbs of force, how much more will the spring compress? In this example, only another 1/2 inch. This is a VERY simple progressive spring, but should illustrate the point..Hopefully you can see the curve starting to develop. Each inch of travel require MORE force than the last inch of travel.
Doesn't matter what "type" of spring we're talking about...compression, extension, torsion. They ALL exhibit this behavior and can be tuned during manufacture.