sway bars..

User avatar
skidmark
Hard Yaka
Posts: 616
Joined: Sun Sep 12, 2010 2:24 pm
Location: hamilton

sway bars..

Postby skidmark » Sat Oct 31, 2015 4:54 pm

Righto needing to think about getting my truck sorted for cert....now I'm pretty sure cert man will want to see a rear sway bar atleast to help with road manners.. but with long travel rear,what are people running? Thought about using the factory saf one but shocks ended up getting mounted where that went. Considered trying to adapt factory front torsion bar with some handmade arms, not sure how it'd work? Haven't measured lengths vs chassis yey

Cheers
modified surf, hardly drive it seem to keep modifying it....

User avatar
bernie
Driver/Navigator
Posts: 39
Joined: Mon Dec 09, 2002 12:00 pm
Location: franklin
Contact:

Re: sway bars..

Postby bernie » Mon Nov 02, 2015 5:58 pm

Might be easier to make one, you'd at least get the "rate" you wanted.
Not sure I'd want to use a torsion bar especially if it's only been twisted in one direction all its life. it's a possibility it could just snap when you start twisting in the opposite direction.

User avatar
Checkerhead
Hard Yaka
Posts: 463
Joined: Sun May 25, 2014 11:20 pm
Location: Christchurch

Re: sway bars..

Postby Checkerhead » Mon Nov 02, 2015 6:39 pm

I don't think that making sway bars out of torsion bars is a new idea. Certainly people have done it before.
Also I don't think twisting it the opposite way would be a problem, it's just a spring. You don't imagine a coil spring snapping if you pulled on it instead of pushing? (I have no facts to back that)
I have been slowly looking at it. Need to find one that is the right length and then has convenient ends for making the arms out of. I've got a Pajero one sitting in my garage for me to do some imagining with.
Supercharged VH45 Surf safari winch truck in the making
viewtopic.php?f=18&t=33527&hilit=checker%2A

User avatar
lax2wlg
Hard Yaka
Posts: 1437
Joined: Sat May 12, 2012 8:33 pm
Location: Various areas

Re: sway bars..

Postby lax2wlg » Mon Nov 02, 2015 6:43 pm

Yeah its a really cool idea. Check out the Anti-rock Sway Bar for Jeeps. It uses the torsion bar principle.
TOYOTA - The Official Vehicle of ISIS!
And makers of the '92 Camry, where you got your first backseat handjob.

User avatar
skidmark
Hard Yaka
Posts: 616
Joined: Sun Sep 12, 2010 2:24 pm
Location: hamilton

Re: sway bars..

Postby skidmark » Tue Nov 03, 2015 6:04 am

Those anti rock is what gave me the idea,just at 7-800 dollars the make it myself looks appealing... had a measure of the surf one it's about 10mm wider than chassis rail..gad a plan where I was going to use the adjuster side on both ends as its not cast like the end that bolts onto the front arm,but different splines on either end...

If possible when you get a chance could you measure overall length of the pajero one?

Cheers
modified surf, hardly drive it seem to keep modifying it....

User avatar
Checkerhead
Hard Yaka
Posts: 463
Joined: Sun May 25, 2014 11:20 pm
Location: Christchurch

Re: sway bars..

Postby Checkerhead » Tue Nov 03, 2015 6:09 am

Yeah I've looked at a few and every single one has different splines on each end. I'm with you on the $800 being a little up there.
Supercharged VH45 Surf safari winch truck in the making
viewtopic.php?f=18&t=33527&hilit=checker%2A

User avatar
skidmark
Hard Yaka
Posts: 616
Joined: Sun Sep 12, 2010 2:24 pm
Location: hamilton

Re: sway bars..

Postby skidmark » Tue Nov 03, 2015 6:19 am

Checkerhead wrote:Yeah I've looked at a few and every single one has different splines on each end. I'm with you on the $800 being a little up there.


I had a feeling that might be the case...I could make the Toyota one work I think, but it'd have two different ways of attaching the arms. One side could be welded onto the spline,but the other bolts as its cast..but that would push it the little bit wider to get past the chassis rails. Hmmm
modified surf, hardly drive it seem to keep modifying it....

User avatar
bernie
Driver/Navigator
Posts: 39
Joined: Mon Dec 09, 2002 12:00 pm
Location: franklin
Contact:

Re: sway bars..

Postby bernie » Tue Nov 03, 2015 6:46 am

I understand the principles of a torsion bar perfectly well and I'm not sayin don't do it, just that there is a possibility....
and at the end of the day finding one that can be modified with the right ends on it that will give the rate you want will be a challenge.
In that respect if you do know the rate, it may just be easier to make it, in my opinion.
There is nothing magical about it. Machine to, the right length and diameter some 4340 bar, spline the ends and heat threat it. The only magical part is knowing what rate you want. (just sayin)

I bet you a box a beer, if you took the torsion bars out of a vehicle and swapped them from side to side, it would sit higher... it may only be 3, 4 or 5mm but, if that's the case, it should tell you something..

User avatar
Checkerhead
Hard Yaka
Posts: 463
Joined: Sun May 25, 2014 11:20 pm
Location: Christchurch

Re: sway bars..

Postby Checkerhead » Tue Nov 03, 2015 7:38 am

Fair point Bernie. And what you are suggesting is certainly superior. Also from what I have looked at, many of the torsion bars lack a suitable surface to run the bushes on. Mainly because they tend to reduce in diameter pretty quickly after the splines. Therefore you would have to use a two piece bush for a lot of them.

Either way the rate is a bit of a guess, I plan to "tune" the rate by adjusting the length of the arms, which will be trial and error. In fact the whole thing is just a "best guess" type of affair really.
Supercharged VH45 Surf safari winch truck in the making
viewtopic.php?f=18&t=33527&hilit=checker%2A

User avatar
skidmark
Hard Yaka
Posts: 616
Joined: Sun Sep 12, 2010 2:24 pm
Location: hamilton

Re: sway bars..

Postby skidmark » Tue Nov 03, 2015 10:31 am

For the most part it's only going to cost me some bushes and probably some Rod ends doe the links and a bit of time.. might make it bolt in so I can experiment with it.
modified surf, hardly drive it seem to keep modifying it....

User avatar
Madaz
Hard Yaka
Posts: 1040
Joined: Mon Sep 05, 2005 12:00 pm
Location: Hamilton

Re: sway bars..

Postby Madaz » Tue Nov 03, 2015 8:52 pm

Does it actually handle that bad without one? Both Checkerheads and my hilux managed to get certed without sway bars???
Braking and noise seemed to be a bigger gripe with them......

Course, it also depends on which certifer your planning on using too......

User avatar
skidmark
Hard Yaka
Posts: 616
Joined: Sun Sep 12, 2010 2:24 pm
Location: hamilton

Re: sway bars..

Postby skidmark » Tue Nov 03, 2015 9:02 pm

Amazingly I haven't taken it for a squirting up the road yet.. I was just thinking they'd want to see one.

Plan on using Neil miller as he's the better one of the two I know of. Noise should be ok as its not too loud.brakes haven't been tested to cert standards yet
modified surf, hardly drive it seem to keep modifying it....

User avatar
Checkerhead
Hard Yaka
Posts: 463
Joined: Sun May 25, 2014 11:20 pm
Location: Christchurch

Re: sway bars..

Postby Checkerhead » Tue Nov 03, 2015 9:20 pm

Yeah Madaz has a very valid point. Do you actually want a sway bar? Definitely mine had issues with brakes, not a power or heat capacity thing, just in terms of manners while under hard braking (which a sway bar may or may not have helped with).

We both used Neal. Pick your battles and be patient. He's reasonable to deal with.
Supercharged VH45 Surf safari winch truck in the making
viewtopic.php?f=18&t=33527&hilit=checker%2A

User avatar
skidmark
Hard Yaka
Posts: 616
Joined: Sun Sep 12, 2010 2:24 pm
Location: hamilton

Re: sway bars..

Postby skidmark » Tue Nov 03, 2015 9:24 pm

Point well taken. Will test it when opportunity arises and make the call...cheers for feedback fellas..
Yes Mr miller did seem to be more resnoble to deal with.the company I work for puts a wee bit of work through the other well known certifier and he didn't even want to talk to me about it before I started.
modified surf, hardly drive it seem to keep modifying it....

User avatar
Madaz
Hard Yaka
Posts: 1040
Joined: Mon Sep 05, 2005 12:00 pm
Location: Hamilton

Re: sway bars..

Postby Madaz » Wed Nov 04, 2015 7:12 pm

Yeah, that other certifer is a interesting critter, had thought about using him at one point, right up to the point where he wouldnt cert my truck with the internal rollcage in it....
Bearing in mind that cage had already been passed by Neal when truck was first certed........

Pretty much as long as you truck pulls up in a straight line under braking, and doesnt wander all over the road you should be fine with neal

User avatar
skidmark
Hard Yaka
Posts: 616
Joined: Sun Sep 12, 2010 2:24 pm
Location: hamilton

Re: sway bars..

Postby skidmark » Wed Nov 04, 2015 7:14 pm

Magic.thats what I like to hear... just went for a a small slow squirting up around the block (closed road of course......) seems to be not too bad considering what it is on silvys
modified surf, hardly drive it seem to keep modifying it....

User avatar
lax2wlg
Hard Yaka
Posts: 1437
Joined: Sat May 12, 2012 8:33 pm
Location: Various areas

Re: sway bars..

Postby lax2wlg » Fri Nov 06, 2015 2:50 am

Good stuff. So Bernie, assuming that the spring rate of a torsion bar is determined by its diameter x length, does that mean that you would be limited in terms of defining spring rate w this setup? Ie the length is predetermined by both the track width and the suitability of mounting locations? So you only have diameter to play with?

My understanding is that they are prestressed to work on a certain direction ie down travel, but obviously they have to twist in the opposite direction for up travel. So they're designed to twist in both directions but due to the prestressing they want to push down.

Off topic but as a suspension system, personally I am over torsion bars. Next is adjustable coilover long travel.

As a sway bar it could work very well. I realized recently that a sway bar is an integral part of a suspension system. Even off road it can help a lot with bow/stern weight transfer, roll center etc. personally I think that for a dual purpose expo rig, sway bars should be a BIG consideration. I've thought about using hydraulic rAms as a disconnect, that's getting pretty far out there though.
TOYOTA - The Official Vehicle of ISIS!
And makers of the '92 Camry, where you got your first backseat handjob.

User avatar
Clint
Hard Yaka
Posts: 632
Joined: Tue Feb 17, 2004 12:00 pm
Location: Rotoiti (North Is)

Re: sway bars..

Postby Clint » Wed Nov 11, 2015 12:34 pm

My cruiser was certified without an anti-roll bar. (by that other certifier :? :lol: )The springs & shocks are moderately firm & body roll doesn't seem to be a problem. I have the front & back anti-roll bars from the axle donor vehicles I could fit fairly easily if I thought I needed them.

One way of tuning a torsion bar based anti-roll bar setup might be to start with the heaviest bar you can find then machine (or grind) a bit off the diameter until it feels right.

Cheers
Clint
UZJ71 Landcruiser
Jeep J20 - 1UZ-FE powered (part owner)
KTM 640

If it breaks, build it stronger.
If it doesn't break, drive it harder.

User avatar
lax2wlg
Hard Yaka
Posts: 1437
Joined: Sat May 12, 2012 8:33 pm
Location: Various areas

Re: sway bars..

Postby lax2wlg » Thu Nov 12, 2015 11:38 pm

One time I was investigating the idea of turning down torsion bars on a lathe incrementally to try to find the best rate possible But I was told by 3 different engineers that this was a bad idea with prestressed spring steel.
TOYOTA - The Official Vehicle of ISIS!
And makers of the '92 Camry, where you got your first backseat handjob.

Return to “Drivetrain / Suspension”

Who is online

Users browsing this forum: No registered users and 5 guests