Outer Limits 4x4 Board

My A-Arm is stuffed and due to be replaced, so firstly if anyone has info on a cheap stockist that would be great. Is there an option with a replaceable ball joint? I haven't pulled mine of yet but I assume its a one piece deal.

Secondly I have read the previous a-arm info posted by Sikid and others and looked at the option of a spacer.

Link

Would this be worthwhile on an OME lift? I was looking at adding a 35-40mm spacer for the new a-arm.

Thanks in advance.

i have been through a number of ball joints. just like your shoulder, when you dis-locate the ball in the socket.

most of the time, the castle nut is loose, and you just need to tighten it up.

i have 4" of lift on the back of my green vit, and super long shocks, which meant the ball in the joint was wearing out the socket when at full flex and droop.

i should have made a spacer.

i now have a 50mm/2" spacer on my white vit, but it only has a 3" OME suspension lift. still using super long shocks, the upper ball joint does not bind and wear anymore.

the upper A arm is a 1 piece unit and last i checked i couldn't replace the bushes in it or the ball joint. so i went to the wreckers and pulled 2 more arms off the wrecked vits for future use and spares.

SPF0921K Rear Control Arm Upper - Inner Bushing
from

http://www.fulcrumsuspensions.com.au/fulcrumCat/

Priced at supercheap at $45 and that has the bushes and tubes for both sides


dont know bout the ball joint but SiKid_01 might be right about it not being replacable.

Suzuki also make the bushes I priced them at 74.40 last time i checked
Edit. I knew i had the part number around somewhere

the rear a-arm bushes are one of these but i dont know which one
# SZ-0931912045 12.2X42.8X65
# SZ-0931912044 12.2X45X65
# SZ-0931912047
# SZ-0931914007 14.2X42X65

any suzuki service centre should be able to type those part no's in and get a schematic showing where they fit


The spacer helped heaps on my vit after a lift. apart from giving the ball joint its range of motion back it also corrects the functioning of the proportioning valve and apparently helps improve the tail shaft angles(?). I had an annoying hum post lift that the spacer corrected

http://stores.ebay.co.uk/Bits4Vits

Dave's got spacers...

PCRman wrote:The spacer helped heaps on my vit after a lift. apart from giving the ball joint its range of motion back it also corrects the functioning of the proportioning valve and apparently helps improve the tail shaft angles(?). I had an annoying hum post lift that the spacer corrected

What size spacer did you use? 50mm?

SiKiD_01 wrote:i have been through a number of ball joints. just like your shoulder, when you dis-locate the ball in the socket...

Thanks for tips.

im sure i could supply cheaper than dave



if anybody is after these just let me know.

=SKB= wrote:What size spacer did you use? 50mm?

Yer, 50mm to match my lift at the rear. Had mine fab'ed from marine ali.

How do these spacers effect your rear suspension geometry ? I cant imagine they would be overly kind to it ..

love_mud wrote:How do these spacers effect your rear suspension geometry ? I cant imagine they would be overly kind to it ..

As far as im aware the a-arm spacer is purely corrective, returning the arm back to its original angle pre-lift. I was more concerned with what the lift itself does to the suspension geometry.

PCRman wrote:

love_mud wrote:How do these spacers effect your rear suspension geometry ? I cant imagine they would be overly kind to it ..

As far as im aware the a-arm spacer is purely corrective, returning the arm back to its original angle pre-lift. I was more concerned with what the lift itself does to the suspension geometry.

That's what I am trying to ascertain. Are they corrective and therefore worth installing? Or are they not really needed on lifts under 3". If I need to fork out for a new a-arm, I don't want to have to replace it again due to ball joint failure from the change in angle created by the lift.

Suspension guru's?

PCRman wrote:
....it also corrects the functioning of the proportioning valve...

(trying not to sound completely stoopid)... why is the A-arm related to a valve on the brakes?

DSzuke wrote: (trying not to sound completely stoopid)... why is the A-arm related to a valve on the brakes?

Not stupid at all. I did not know i had one until i started looking at lifts.
The a-arm is hooked up to the PV via a spring. As you load the car up it sits down at the rear. As the a-arm is connected to the diff at a ball joint and by the tubes and bushes on the body the effect of loading the car is to make the a-arm become more horizontal. this allows the spring hanging of the front of the a-arm to relax which removes pressure from the valve allowing the rear brakes to do more work compensating for the increased load.

At least that is how i understanding it to work. I found that the easiest way to undersatnd how it functions was to lay underneath while someone bounced the zuk up and down

PCRman wrote:
...lay underneath while someone bounced the zuk up and down

I'd rather be one of the persons bouncing the zook

PCRman wrote: As far as im aware the a-arm spacer is purely corrective, returning the arm back to its original angle pre-lift. I was more concerned with what the lift itself does to the suspension geometry.

Not quite.

The spacer WILL change suspension geometry. Increasing the link separation by raising the centre link will raise the roll centre and increase antisquat.

Neither of these parameters is affected by suspension lift with the rear suspension design of a vitara.

I've built a relocation bracket recently (raised the link mount 50mm and brought it forward 26mm) and it seems to have worked out well for the car, and has avoided having to remanufacture the A arm to pass engineering. It does seem to be a valid fix, so I'm not knocking it as a solution, but it will effect geometry.

As an aside, I believe lowering the chassis end of the link is preferable to raising the diff end. Doing this will reduce antisquat which I have a hunch will improve suspension behaviour on vitaras. Vitaras already have a much lower fron roll centre than rear and this leads to tricky high speed handling, It's one of the reasons I'd prefer to see the rear roll centre stay where it is on the back.

Just some thoughts. The spacer is by far the easiest way of eliminating bind which is very bad. I've also noticed that the stock calmini heim joint (apart from being a VERY low quality unbranded part) binds on its bushes too )

Steve.

Gwagensteve wrote:Increasing the link separation by raising the centre link will raise the roll centre and increase antisquat.

Mmmm, I forgot to consider the effect that the spacer would have on roll centre, no argument there Steve. But I would have said that if the addition of the spacer returns the angle of the a-arm relative to the chassis to what it was before a lift isn't the antisquat the same as what it was before? (granted the antisquat HAS in reality been changed by the new angle that the trailing arms make with the chassis).

What about dropping the a-arm at the chassis end as you suggested for maintaining roll centre as well as dropping the trailing arm mounts at the chassis end? Does having zero antisquat mean having the arms (A- and trailing) horizontal relative to the chassis when the car is stationary?

One thing I wont disagree about is the cornering at high speed after the lift went in, Very scary

No, Antisquat isn't specifically a function of how parallel the arms are. It's a function of the car's centre of gravity, the instant centre of the suspension, link length, link separation and a few other things.

Assuming all other things stay the same, increasing link separation at the diff end will, AFAIK, increase antisquat.

Roll centre for 3-links (like the rear of a Vitara) is at the ball joint on the diff. It doesn't matter how high the chassis end of the A-arm is (ar where any of the other links are), the roll centre will be through that joint. Raising the ball joint 50mm will raise the roll centre 50mm.

Apart from eating into ground clearance, lowering the chassis end should lower antisquat, but between the two modifications, you may well end up with some strange behaviour as the instant centre is going to go way forward when combined with the A-arm lift at the diff end.

Personally, if you're planning any non reversible geometry modifications (like lowering link brackets) I'd plug some numbers into a 4 link calculator to see if what you were planning was going to work.

To expand on my hunch, Vitaras are very "nose" led, both on and off road. They'll pick the rear end well before the front. lowering antisquat should, by my figuring, increase rearwards weight transfer under power and make the rear end work harder.

Interestingly, there seems to be two schools of thought on antisquat - some buggy 4-link builders seem to think that high antisquat is required to provide bite, while others think lower antisquat works best. My Gwagen has VERY high antisquat as it's a radius arm design and I don't like it's behaviour all that much under heavy climbs. I think it'd prefer it to squat more, I think it leads to more predictable behaviour.

Steve.

I've been trialing a few prototype spacers and just thought I would post a few pics here for comments/ideas.....

[img][img]http://i217.photobucket.com/albums/cc10 ... 8Large.jpg[/img]

[img][img]http://i217.photobucket.com/albums/cc10 ... 9Large.jpg[/img]

[img][img]http://i217.photobucket.com/albums/cc10 ... 0Large.jpg[/img]


cheers....

That spacer looks better than the last one I saw

The ball joint boot looks cool too