Tuning a 4 link

[Brenton 86]

Hello all,
Just wondering if anyone has any info on how a 4 link should be adjusted. I finally got one but i have no idea what angle to set it at :S. I don't street drift and i don't have a suitable event to test and tune, so any help will be appreicated.

[Gilly]

set them to same length as stock

to do this get the 2 upper arm body end bolts (long ones) and pu them through your old arms, now adjust the new arms so they slide over the bolts as well.

this will give you a good start point. I find there is a notable increase in performance just from switching to Rose Joints.

from here you can determine whether you need more grip or slip

i've always been of the opinion that adjustable 4 links be used to "correct" pinion angle, not further manipulate it so i would be making the top arms longer and bottom arms shorter to correct it.

maybe try adjusting the the bars one full rotation at a time and see what effects that has

they are fiddly to set up, i'll admit that and they are/can be pretty noisey (especially if you have a noisey diff!!) but they are a sound investment

[Anthony]

in my limited experience on the subject. pinion pointing higher = less grip and more tramping, pinion pointing lower towards ground = more grip.

Come out to the SD full day private day at QR and tune it to your hearts (and tyre stacks) content. :)

[Dom86]

What both the above said. also take into consideration 'ride hieght'.

Basically you want your diff angle to be horizontal (with the tail shaft) under accelleration.
thats what i was told by susspension dudes anyway.

[Gilly]

this seems to be such a "black art" in regards to angles etc

i was always told you wanted the diff nose to be brought back up to horizontal and thats what the adjustability caters for.

I have seen 3 different branded 4 links now and all when adjusted to "stock" arm length allow moreso for correction only, not allowing much scope for the nose to be pointed further downwards.

you can see in the pic below that once adjusted to stock length the lower arms have ample room to be adjusted shorter and the uppers a have a good range of lengthening adjustment, by doing so the pinion angle is brought back "up" closer to the horizontal plane.

http://www.ae86drivingclub.com.au/dcimages/4/8/4/3/165424.jpg

A lot of axle tramp can be eliminated through Traction brackets, whilst the 4 links can be tuned to eliminate some, the fact remains that once the car s lowered the angle of the trailing arms (not the diff nose) allows the diff to try and "roll over" itself in the same direction of the wheels (anticlockwise in forward travel)

the combination of both traction brackets and a 4 link will correct both the diff pinion angle and the trailing arm angle thus returning the specs close to stock (or better) whilst still retaining the lowered ride height.

I know traction brackets aren't the topic here but they are useful (i've only learnt this lately and still more to learn obviously) and an esential when reducing axle tramp.

i'm in no way well learned in these practices so any/all information if incorrect please contest!!!

[rockstar]

http://www.ae86drivingclub.com.au/dcimages/4/8/4/3/165466.jpgdoes anyone know what degrees should the pinion angle be setup as for traction cause i need to set mine up and i can't remember, maybe it -3 or +3 degrees rings a bell for some reason

[af300e]

My research suggests the following. The anti-tramps are what change the anti-squat/anti-dive. These settings are what is important. Changing the lengths of the arms has an effect but it is, as has been said, more to do with getting the rear uni alignment correct. Changing the height of the front or rear of the arms is what has the greatest effect on handing. Less anti-squat=less traction under power. Naturally, when you change the height of the link mounts, you may have to adjust the length of the arms to re-align the diff uni, and this I believe, is why the adjustable arms exist.

[Brenton 86]

cheers guys!, sounds like i should just bung em in and maybe just try to bring the pinion up abit.

[Os7213]

Hi everyone!

I know I'm not a regular member of this forum
But I think theses few infos can help you with 4link and traction brackets adjustments:

http://img522.imageshack.us/img522/6851/4link5tz7.jpg (http://imageshack.us)

http://www.ae86drivingclub.com.au/dcimages/4/8/4/3/165453.jpg (http://imageshack.us)

Basicly a good pinion angle is about 4deg and if I remember well an adjustment of 20mm of the 4link arm is about 1deg pinion angle.
But I'm not totally sure so plese use this mesurement with attention.

Hope that help
Hugo

[stefan]

<div class='quotetop'>QUOTE (NA workz @ Feb 28 2008, 06:59 PM) <{POST_SNAPBACK}> (index.php?act=findpost&pid=494555)</div>
http://www.ae86drivingclub.com.au/dcimages/4/8/4/3/165466.jpgdoes anyone know what degrees should the pinion angle be setup as for traction cause i need to set mine up and i can't remember, maybe it -3 or +3 degrees rings a bell for some reason[/b]


what way did you mount your traction brackets?

did you just drill a new hole and bolt in?

how much more noticable is it with 4 link and tracktion brackets?

[samuel]

Please add all of this to the FAQ