so a few years on and a few more changes. Last year worked o n the geometry a bit more and got a more stable off roader. did this by moving the front axle as far forward as possible. in so doing the tall sump of the 2F engine satd BEHIND the diff tube and also lowered the engine a few inches. Moved the rear axle forward as well to give the same wheel base more or less, and maintained the unimog torsion tubes - which we cut and altered to size.
this resulted in a lower over all body height and better weight distribution, the engine and gear box being more centered.
Also the holley carb was performing below spec, and cutting off at steep angles. SO replaced this with the stock carb which worked great, at any incline.
However - I cooked the 2F engine at the last event, and with the BIG one coming up Rhino Charge 2014, the choice was to either bolt on a 3F which was available, and run it through the unimog gear box (which I also converted to 8 speed last year - 4 gears high ratio and 4 gears low)..... OR
get a V8 in there and put serious horse through the portal axles.
while at it, put in a more substantial suspension system, working with what we had available.....
the result: a UNILINK system with a TOYOTA V8 2 UZ FE engine, automatic gearbox, to run the portals and 42 inch tyres.
the idea was to make A frames to each axle hinged in the centre on the 'ball" of the unimog torsion tube.
This pig sits on a unimog 404 chassis - which gives it huge amounts of flex, the need to prevent axle wrap and breaking the propellors, housing, would be overcome by the A frames. the ball would allow any degree of rotation and up and down movement, the A frames prevent wrap.
so welded a chunky plate (from a truck chassis) at the centre of the chassis.
machined up a plate that was the same as the end of the gearbox housing on the unimog, for both sides, and mounted the cut off torsion tubes to this.
using 4 x 2 x 6mm sections and plate, made up the A frames. had to machine some flange adaptors for the diff pinion shafts, and bung an oil seal in there. used the TOYOTA propellors, though these would have to be cut to size...
for the front portal axle to line up with the TOYOTA gearbox, the diff had to be 'flipped' over to achieve this.
with the vehicle set on the bump stops we lowered the 2 UZ onto the chassis. the front propeller rake is steep, and a result of the flipped diff is the caster and camber is WAY out .... but, things lined up quite satisfactorily.
assembled everything up, and had a test run. the transfer case was not in good shape, and the rake angle on the front prop shaft made for some interesting sounds, so played around with all that a great deal to get it right. time to test it and then fit the new bucket seats and clean up the interior.