Caster

[red90 driver]

Does anyone have any sound words of advice regarding setting up a challenge truck with rear wheel steer?

I am playing with a Disco 2 front axle with a view to using it as a basis for a hydraulically controlled steerable axle.

So far,

I will probably use a single ended ram, 50mm bore, 200mm stroke and 25-30mm rod diameter, pushing/pulling on the knuckle while a drag link arrangement ensures both wheels turn together.

I want to know what power steering pump will have enough flow and pressure to run the rear axle while still using the standard (if possible) steering box on the front? I've had a look at some of the stuff that PSC in the states are selling but not had a reply from them yet.

Would I also transfer the knuckles from this front axle onto a rear axle, or mod the front axle to fit onto the rear? I'm already using airshox and modded disco 2 front arms....

what sort of caster angle for the rear? People on pirate seem to suggest either 0 degrees (for low speed) or somewhere around twice the front caster angle for higher speed self centring..

[dirtydiesel]

I would run about 6 degrees of caster, and i'd probably be choping the swivels onto your rear axle.

I'd be using a seperate pump, A 50x30x200 single ended ram will work very well off a ported 300tdi pump,

[red90 driver]

Will that same pump also run the std steering box as well?

With regards to the force exerted by the ram, I've got the calcs, but have no idea about what pressure and flow a ported 300TDi will give.....

If I could drop onto a ZF74 pump, would that be the better option?