Hey neighbor!

What exactly are you talking about? Did some "tuner" tell you that.
Are you refering to "cranking" the torsion bars?

 

Winding up the torsion bars is most often used to give the car a front suspension lift, but it can inprove the handling on a car that is stock, as if the car is a few years old its very likely the front suspension will have sagged a little over time, so tweaking the bars up a little will tighten the handling and bring the car back up to stock hieght.

 

Yes...but just to clarify you aren't "tightening" the torsion bars at all, you are just adjusting ride height when you "crank" the torsion bar. Remember that both ends of the bar move when you crank it, so the tension doesn't change.

 

Yes...but just to clarify you aren't "tightening" the torsion bars at all, you are just adjusting ride height when you "crank" the torsion bar. Remember that both ends of the bar move when you crank it, so the tension doesn't change.

WHAT!

when you screw the adjuster in further or "crank the bar" you are increasing the so called spring rate of the bar and putting more force on front control arms to provide more lift. you are twisting the bar further.

you will also get a stiffer ride (expecially if the bars arent that old).

but to answer the question no you wont hurt the frame if you modestly lift the vehicle.

 

No, BigSwede is right. The spring rate remains the same. Cranking one end of the bar moves the other end. The weight of the truck is the only thing pushing back on the t-bars, and that doesn't change when you crank them, it just changes the setpoint.

Won't damage your vehicle at all. Mine are cranked 2.5" higher than stock. Put some jack stands under there when you're cranking.

 

NO think about it,

how can the other end move while you tighten the adjuster. it doesnt its splined to the control arm.

yes the vehicle is pushing back at the bar but in order to make the bar do more work (lift the vehicle higher) you are putting more twist in it and thus incresing the bars power to make the vehicle higher.

 

say you twist 1 end up a 1/4 of an inch the other end is going to push down a 1/4 of an inch and at the end of the a-arm that may translate to 1/2 inch...hypotheticlly of course..

 

incresing the bars power to make the vehicle higher

Hahahaha. Increasing the bars power huh? I weep for BMWs.

Seriously, the vehicle doesn't weigh any more, and the torsion bars are not doing more work, you are simply adjusting the ride height. The only reason the ride is rougher afterwards is because you are decreasing the downtravel (therefore running into the bumpstops more often) and because the control arms are sitting at a different angle, which affects the suspension geometry. The torsion bars have the same spring rate, that is impossible to change.

As far as it being bad for the frame, possibly yes, it may lead to more jarring when hitting large bumps, but its pretty negligible. Your frame is more likely to die from rust then cracking.
________
Plymouth (Automobile) History

 

how can the other end move while you tighten the adjuster. it doesnt its splined to the control arm.

The control arm that the other end of the t-bar is splined to moves down as the adjuster is tightened. Each crank of the adjustment bolt raises that side of the front end a certain amount. I watched this happen first hand as I adjusted my own.

 

Sorry 90turbo1, but you are completely wrong on this one. You have failed in your understanding of the basic mechanics of a spring. Spring rate (force per deflection), is calculated ONLY from the physical dimensions of the spring. In the case of a torsion bar, these dimensions include the length and diameter of the bar. For a compression spring, the free length and number of coils is also taken into consideration. If you do not physically change out the spring on your truck, the spring rate remains the same.

When you "crank" your torsion bar, the only thing that can possibly change is the spring's preload force. Let's say, for the sake of argument, that the static force on one corner of the truck is 500 lb. You cannot generate more than 500 lbs of preload with the truck just sitting there, so if you crank after this point the corner will LIFT. I don't know what setup BMW's use, but I imagine that some of them would be coil-over (especially if it's aftermarket). Cranking the t-bar is the same concept as raising or lowering the spring perch to change the ride height of the car.

Now the reason that you will get lift is just as Desertbenny says, the torsion bar will rotate. Yes it is splined into the a-arm, so it does not physically spin. But the a-arm is not fixed, so this rotation force (torsion) is transferred through the a-arm and the a-arm will turn about its pivot point. See the diagram I made below:

Hopefully this clears things up for you a bit. I'm not trying to be harsh, but your understanding is a bit off....take it from an engineer.

 

jdstuf,
You should make your arrows spin the other direction so it shows the torsion bar 'lifting' the control arm. Just for kicks.

 

jdstuf,
You should make your arrows spin the other direction so it shows the torsion bar 'lifting' the control arm. Just for kicks.

Yeah, the pic I drew is a force diagram. I guess I just assumed that it was implied that if there is a force on the end of the a-arm acting down, then the truck is going to move up......ya know, equal and opposite. :wink:

 

Rodeo Raymond,
The torsion bars are what they are. You can't change how strong they are or how stiff they are. They're already holding up the weight of the front end of your truck as it sits right now.
If you "tighten" them, as you said, all you will do is raise the height of the front end.
If you "loosen" them, you lower the front end.
You won't change how firm they are.
But a couple of things will happen besides raising the truck:
1. You will loose some down-ward travel of the front suspension, because by raising it, the control arms will be closer to the bottom of their suspension travel. Kind of the same effect as when you jack it off the ground and let the suspension droop all the way.
2. You will change the alignment and if you intend to keep it at the new height, you should get it aligned so the tires don't wear funny and you don't have odd handling characteristics.

 

jdstuf,
You should make your arrows spin the other direction so it shows the torsion bar 'lifting' the control arm. Just for kicks.

Yeah, the pic I drew is a force diagram. I guess I just assumed that it was implied that if there is a force on the end of the a-arm acting down, then the truck is going to move up......ya know, equal and opposite. :wink:

I see, that makes sense. That's why you're the engineer and we're not. :lol:

 

so im getting a bad tread wear on my tires they are loosing rubber on the inside qicker than the out so by cranking them puppies you think that'll change it? or is that the wrong way to do it

 

It would be a crapshoot. You probably just need to get it aligned

 

cranking the bars will cause you to ride MORE on the inside of the tire till you get it aligned. You may have worn ball joints that will have to be replaced before they can align it, cranked or not.

 

ok can i hear if my ball joints are worn? haha because when i turn right my left tire bumps and what not and vice versa

 

Could you narrow-down that “bumpâ€

 

cranking the torsion bars TOO far and driving to moab from salt lake city can destroy your CV axels :lol:

 

its like a clunk