My maxed out suspension lift :)

[SlowPro48]

Sorry Beau, but I just can't get past the fact that the same amount of force is required to lift the same amount of weight to the same height. It shouldn't matter if the bar ends are in position "A" or position "B"...

From the torsion bar's viewpoint, it DOESN'T matter - as long as the VX is just sitting there...

When you're actually using your suspension travel, however, it DOES matter!

For the sake of discussion let's say there's 1,000 lbs on each corner of the VX and the distance between the center of the torsion bar and the hub is 1 foot - so with the VX just sitting there, the torsion bar feels 1,000 ft-lbs of torque. Like you pointed out, unless you've cranked so much the suspension is topped out, the only significant variables involved are mass of VX, gravity and length of lever, which are all constant.

BUT - let's say you take that stock ride height VX out for a spin, hit a big G-out and bottom the suspension. Let's also say for the sake of discussion front suspension travel from normal ride height to bump stops is 5 inches and spring rate is 300 lb/inch* - so at the point of bottoming out, your torsion bar feels 2,500 ft-lbs of twist. You hate bottoming out so easily though - so you raise the ride height a couple inches by cranking the torsion bar. Now you've got seven inches of travel from ride height to bump stops. Sweet! You can go even faster through that G-out before you bottom out the suspension - at which point the torsion bar now feels the effects of 3,100 ft-lbs of torque (two more inches at 300 lbs/inch = 600 ft-lbs more torque) and like any other spring it probably doesn't like being twisted by 3,100 ft-lbs as much as it does 2,500 ft-lbs...

Cranking the torsion bar increases ride height but that's just a side effect of increased pre-load. It's fine for small adjustments but Ascinder's method adjusts ride height directly, allowing you to keep pre-load within stock range even for larger adjustments to ride height.

*yeah I know - proper units for spring rate of torsion bars would be in force/angle but lever length is same so using force/distance doesn't have any bearing on outcome - for that matter, all these numbers are made up for simple illustration purposes

[Ldub]

Cranking the torsion bar increases ride height but that's just a side effect of increased pre-load. It's fine for small adjustments but Ascinder's method adjusts ride height directly, allowing you to keep pre-load within stock range even for larger adjustments to ride height.

So by this theory, reindexing the torsion bar "magically" reduces the amount of force required to lift a given amount of weight (load) to the same height?

OK, if you say so...

At this point, I'm willing & able to agree to disagree...

Also, reindexed or not, the suspension travel from like heights, through the full available motion (when it hits the bump stop) is the same, creating the same amount of torsional force for a given amount of travel.

[tom4bren]

The bottom line is that it appears safe to lift 3" using the torsion bar crank (been proven on a fairly large number of our VX's). If you need to go much higher than that though ... better start looking at other options such as a body lift.

[ZEUS]

The bottom line is that it appears safe to lift 3" using the torsion bar crank (been proven on a fairly large number of our VX's). If you need to go much higher than that though ... better start looking at other options such as a body lift.

HEY! You keep your clear water comments to yourself!

[tom4bren]

HEY! You keep your clear water comments to yourself!

Now let's talk about tie rods ... do whatever you want to those ... they never break.

[ZEUS]

Now let's talk about tie rods ... do whatever you want to those ... they never break.

Well actually... with an offset from Hell...

[SlowPro48]

Ldub - I see what you're saying - had to do a little more visualizing there. You're right. I'm wrong. As long as the torsion bar is not pre-loaded to the point where the suspension is topped out, it doesn't matter if the lift is achieved by reindexing or by cranking the torsion bar - when ride height is increased, suspension travel from "baseline" to bump stop is increased - therefore max torque the torsion bar can experience is increased the same amount no matter which method you use. If you crank past the point you're topped out you would increase the max torque seen by the torsion bar, however, as each ft-lb of preload at the top of travel is a ft-lb added at the bottom of travel. But I doubt if anybody would keep cranking after the VX stops going up. There's probably not that much adjustment range is there? You'd have to re-index to do that! OK I gotta get back to my crack pipe now. Thanks for the mental excercise!

Tom - Yeah there's no problem with safety - I wasn't saying that. It's just that the VX won't handle as well if you crank so much preload in that you're riding way higher in the stroke than the designer intended. At three inches higher than normal ride height you're probably not that far from being topped out. When off-road racing on two wheels you want race sag (that would be the equivalent of VX ride height with you and your gear in it) to be set so that you're about 1/3 down into the stroke and I imagine it's a similar setup for best suspension compliance when you're in the four wheel realm too. It's not good for handling/traction if you're topping out all the time. But then I guess the aim here isn't good high speed off-road handling anyway is it? Nobody's running in a rally or a SCORE desert race or anything - they just want more ground clearance to prevent getting hung up and keep from ripping stuff off the bottom of their VX as they crawl over rocks!