Ball joint beam om link pin chassis...Possible?
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Bruce2
- Posts: 7087
- Joined: Sat Oct 13, 2001 1:01 am
Re: Ball joint beam om link pin chassis...Possible?
What about taking a BJ beam and chopping it into two pieces through the shock towers, then move the two tubes closer together?
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Ol'fogasaurus
- Posts: 17761
- Joined: Mon Nov 13, 2006 10:17 pm
Re: Ball joint beam om link pin chassis...Possible?
This is out of the off-road forum and we were talking about ways to get more travel out of a BJ bam. One of the offers out there uses using ball-joints and another uses K&L trailing arms both on a BJ width beam to get longer travel. NOt what this string is about but there is some information in the strings that might help this topic.
viewtopic.php?f=28&t=143369&hilit=K%26L ... in+BJ+beam
Putting the BJ trailing arms in a K&L beam would also have geometry problems as when putting K&L arms into a BJ beam as shown in the URL above. The two spindles have different lengths as well as the trailing arm fitting into the beam itself as I understand it (see the URL on this). I think there is an end seal problem also between the two beams.
viewtopic.php?f=28&t=146341&p=1209838&h ... m#p1209838
The other string was about the bugzilla beam which puts K&L parts in a wider BJ beam. It only uses part of the travel (geometry... see pictures) potential but it is out there.
Right now modifying the K&L frame head or changing over BJ frame head might be the only two answers.
viewtopic.php?f=28&t=143369&hilit=K%26L ... in+BJ+beam
Putting the BJ trailing arms in a K&L beam would also have geometry problems as when putting K&L arms into a BJ beam as shown in the URL above. The two spindles have different lengths as well as the trailing arm fitting into the beam itself as I understand it (see the URL on this). I think there is an end seal problem also between the two beams.
viewtopic.php?f=28&t=146341&p=1209838&h ... m#p1209838
The other string was about the bugzilla beam which puts K&L parts in a wider BJ beam. It only uses part of the travel (geometry... see pictures) potential but it is out there.
Right now modifying the K&L frame head or changing over BJ frame head might be the only two answers.
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Ol'fogasaurus
- Posts: 17761
- Joined: Mon Nov 13, 2006 10:17 pm
Re: Ball joint beam om link pin chassis...Possible?
Couldn't get to sleep last night so I amused myself with some mental gymnastics.
Assuming you could take the two suspension tubes from a BJ beam and mount them properly into the mounts for a K&L beam (see the previous post for tube size differences) there is some good and bad: I think either the K&L shocks would work if you did some mods to make the shock mounts fit the BJ K&L shocks/dampeners are eye and eye while BJ shocks are eye and post) and the steering box and tie-rods might/shouldn't be a problem to mount assuming you use BJ tie-rod ends (I'm not sure if there is a difference so I bring this up).
I don't have anything with me to do a layout and also what the BJ max angle would be so here is what I think would happen: The BJ arms, with the spindles mounted, are not going to sit ~parallel as they would in a stock BJ beam; the upper arm will sit at an angle with the BJ mount facing slightly up and the lower arm will sit at and angle with the arm facing slightly down (no good idea of that angle would be but it should be fairly easy to figure out). The hitch with the beam mod would be by the BJ itself; in off-road we can get to use something like 4" to 6" of travel which is dictated by the angle limitation of the ball-joint spud max angle (I think you might want to add hook and pin stops to protect yourself). Since the join between the spindle and the two ball-joints is going to/has the potential to reduce some of the suspension travel potential... I think.
I don't know what the BJs limit angle is and using the modified BJ that some off-road racing classes allow might help some regaining of the BJ angle but I seem to remember they wear faster (at least off-roading they do) and may be a bit weaker.
Since I think the Thing front end was brought up some info: as far as strength goes, the Thing design is going to be stronger then a bug beam but the spindle's spud is mounted lower on the spindle allowing the front of the car to sit higher which I don't think is what you are after. The mounting of the lower ball-joint is different as the BJ spud is facing down rather than up which eliminates the problem with stock BJ from pulling out of the lower training arm. The Thing spindle itself is longer to accommodate the change in the lower BJ mounting. The upper BJ is mounted as normal bug but it's BJ spud is bigger in diameter to accommodate the loading changes in the trailing arm/spindle assembly. Since the BJ spud is slightly larger in diameter which could affect angle a bit more. The other drawback is the adjuster which has the hole for mounting it to the BJ a bit larger in diameter and very hard to find (and can be expensive).
Again, this is an unsubstantiated opinion done late at night
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Lee
Assuming you could take the two suspension tubes from a BJ beam and mount them properly into the mounts for a K&L beam (see the previous post for tube size differences) there is some good and bad: I think either the K&L shocks would work if you did some mods to make the shock mounts fit the BJ K&L shocks/dampeners are eye and eye while BJ shocks are eye and post) and the steering box and tie-rods might/shouldn't be a problem to mount assuming you use BJ tie-rod ends (I'm not sure if there is a difference so I bring this up).
I don't have anything with me to do a layout and also what the BJ max angle would be so here is what I think would happen: The BJ arms, with the spindles mounted, are not going to sit ~parallel as they would in a stock BJ beam; the upper arm will sit at an angle with the BJ mount facing slightly up and the lower arm will sit at and angle with the arm facing slightly down (no good idea of that angle would be but it should be fairly easy to figure out). The hitch with the beam mod would be by the BJ itself; in off-road we can get to use something like 4" to 6" of travel which is dictated by the angle limitation of the ball-joint spud max angle (I think you might want to add hook and pin stops to protect yourself). Since the join between the spindle and the two ball-joints is going to/has the potential to reduce some of the suspension travel potential... I think.
I don't know what the BJs limit angle is and using the modified BJ that some off-road racing classes allow might help some regaining of the BJ angle but I seem to remember they wear faster (at least off-roading they do) and may be a bit weaker.
Since I think the Thing front end was brought up some info: as far as strength goes, the Thing design is going to be stronger then a bug beam but the spindle's spud is mounted lower on the spindle allowing the front of the car to sit higher which I don't think is what you are after. The mounting of the lower ball-joint is different as the BJ spud is facing down rather than up which eliminates the problem with stock BJ from pulling out of the lower training arm. The Thing spindle itself is longer to accommodate the change in the lower BJ mounting. The upper BJ is mounted as normal bug but it's BJ spud is bigger in diameter to accommodate the loading changes in the trailing arm/spindle assembly. Since the BJ spud is slightly larger in diameter which could affect angle a bit more. The other drawback is the adjuster which has the hole for mounting it to the BJ a bit larger in diameter and very hard to find (and can be expensive).
Again, this is an unsubstantiated opinion done late at night
.Lee
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Steve Arndt
- Posts: 7404
- Joined: Sat Mar 10, 2001 12:01 am
Re: Ball joint beam om link pin chassis...Possible?
Quite possible.Bruce2 wrote:What about taking a BJ beam and chopping it into two pieces through the shock towers, then move the two tubes closer together?
I'm doing the same but reversed. Chopping a link pin warrior beam to stretch it ~1" vertically to achieve ball joint pan head spacing.
Steve
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Marc
- Moderator
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- Joined: Thu May 23, 2002 12:01 am
Re: Ball joint beam om link pin chassis...Possible?
Physically possible, perhaps, but not advisable for a street rig. If it worked, people would've been doing this for the last 40 years....have you seen one on the road?
Viewed from the side, the beam, control arms, and spindle comprise a functional parallelogram. If you change the length of any side of a parallelogram, A) it's no longer a parallelogram and B) the suspension will no longer work as designed...in order for the spindle to move up and down, something has to give - the spindle must tilt and/or twist. Tilting is relatively benign (it makes the caster angle change drastically as the suspension cycles, but on dirt nobody seems to mind) but on a ball joint front end there's also a tendency for the ball joints to @@@@ and allow the spindle to pivot, causing some ugly bump steer.
http://www.mathopenref.com/parallelogram.html
Viewed from the side, the beam, control arms, and spindle comprise a functional parallelogram. If you change the length of any side of a parallelogram, A) it's no longer a parallelogram and B) the suspension will no longer work as designed...in order for the spindle to move up and down, something has to give - the spindle must tilt and/or twist. Tilting is relatively benign (it makes the caster angle change drastically as the suspension cycles, but on dirt nobody seems to mind) but on a ball joint front end there's also a tendency for the ball joints to @@@@ and allow the spindle to pivot, causing some ugly bump steer.
http://www.mathopenref.com/parallelogram.html