Proportinal force of spring effects on full drop
 

Most people who use full drop insert a spring in the shock body. The spring help the shock to keep or to return to its compressed state during a climbing or a lateral slope.
Can you suggest good shocks and compatible springs ? I bought Integy MSR10, expecially developed for drop, but they are HUGE, I would need something a bit smaller, at
least in the diameter.
In a crawler shocks are normally mounted inclined, the angle changes when the axle moves vertically and they are more inclined when they are full compressed. A spring
exercise a force which is proportional to its compression. So, when you are near full compression there is a little force exercised by the spring which tries to close the shock
and the greater inclination reduces the useful component too. So there are two factors who both reduces the force when the shock is almost fully compressed, the greater
inclination which reduces the useful component and the proportional force of the spring. The overall force exercised by the spring is limited by the weight of the axle, otherwise
it may not go down when the crawler is high centered. I wonder if somebody has succesfully find a way to reduce these effects: I believe that a constant force during all the
vertical travel of the axle ,a bit smaller than its weight, would be the optimum, but I may be wrong.
One way to have a constant force would be the replacement of the shocks with pneumatic pistons connected to a 'big' air tank who keep the pressure almost constant.
Probably using some kind of cantilever you can counter balance the ill effect of the greater inclination at the limit but I don't know how.

Thanks
Filippo

Wow. You're making this way to complicated. You can swap springs, if you want, until you get the desired spring action, and just about any normal sprung shock can be changed to an internal droop set-up. You also need to take into account the shocj oil. Normally, you will run a heavier oil in a droop suspension set-up because you cannot rely on the spring alone to slow the action of the axle dropping. Something like 70-100 weight oil works good. Some go further by using diff fluid of even heavier weights. It's a matter of playing with shock pistions, piston hole sizes and the number of holes in the pistion, spring strength, and finally shock oil.

What I mean is than if the terrain is very inclined it is easy to have the nose a bit rised with the internal springs which cannot bring it back to its steady state because they don't give enough force. According to me it is useless to change the springs with stiffer ones because anyway the force is proportional to their compression and so they are of little help when they are almost at their normal size. In otrher words with a full drop setup I think it is difficult to have a crawler which has all its shocks fully compressed during hard climbs and lateral slopes.

Mine will climb/sidehill 60 plus w/o unloading. I kinda found some springs with a rate that would hold in the chassis (shocks compressed)when vertical. Stiffer springs in front due to weight bias and softer in rear. The spring hold the chassis' weight, but allow the axles to drop since they outweigh the chassis. Oil thickness will control reaction speed.
Also, I found that too much or little antisquat will affect how the chassis will rise (antisquat) or fall/suckdown (squat). I found a more neutral vertical seperation of links works well with droop, but others like a little squat.
Tried adding squat and it didn't work for my style (too 'stiff'), but every driver is different. hope some of this helps. Good luck!