Well, Beau, I'm confusaled with ya! OK, the distance between the fronts of the arms related to the rears is always equidistant because of the design of the arms you are looking at eliminate the Ackerman principle... the "issue" that I bring up is that since 3 sides of the parallelogram are of static distance but one side is not, pressure is put on the tie rod - the weakest of the 4 sides. With what I just did in Cad, based off the dims you gave me, the deflection of the tie rod will be 7/32" or just over 3/16" with an 8" stroke. Because of this, I would say stay away from the long tie rod bridging the arms together. However, with those dims, you only get 31 degrees of steering if the ram was mounted 6" off axle center (which would be inline with the arm at 40 degree steer)! I just cannot see how they are getting 80 degrees of steer from lock to lock with an 8" stroke and an 8" straight arm! An 8" arm would need a 10" stroke to accomplish 40 degrees each way in this example because the Ackerman angle is nonexistent in the design of the arms. That is just what I have found - again, I could be wrong or missed something. PLEASE school me if you find out how they make it happen.
Otherwise, in the case of the more desirable way and the most desirable way - I see little difference but it seems the more desirable way is simply the middle ground between the other two options. I'm going to go work on my Army truck now - it's far more simple!!! 
Do you have CAD? I can send to you what I have so you can see what I see happening... Happy researching! 
Originally Posted by
Ascinder
I see what you are saying, but it just stands to reason that if the fronts of the arms must remain parallel so your tires are both steering the same axact angle, then the rears must too, does that make sense? That would mean that throughout the movement of the tie rods, as one increased it's arc, the other would simultaneously decrease it's arc at the same rate which I would think would balance out. The other issues I am having are that I was reading over at pirate that people have basically said this won't work in theory or on paper, but there are people running it problem free. It's very confusing trying to sort through all the contradictory information. I think I may make a model out of PVC and some plywood to real world test this. Also, I wanted to ask if you saw an incredibly big difference between the more desirable and most desirable mounting methods. They look about the same except the ram is deflected to the right in one and centered in the other. Another note is that most hydro steer arms I have heard of mount up on 8 or 9 inch centers. I dont know if that matters, but there you go, they did mention proper Ackerman angle as the reason for that though. Also the rams I have been looking at are typically 8" throws for ~40 degree steering and
10" for 50 degree if you get the U joints machined. Here's also the prints for an example 8" ram(not the one I'm using, but close enough)
The pivot centers of the kingpins are approximately 53.5" as I assume the forward tierod will be as well.. The tierods for the ram are obviously whatever lengths they need to be to set up properly. Hope this helps, I'm crossing my fingers.
Sent from my "two hands on a keyboard"
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