A guide for setting up Anti-Roll / Sway / Stabilizer Bars
One of the questions I get asked a lot is how to set-up Anti roll bars (Or Sway bars / Stabiliser bars etc), so I thought I would just ma...
https://www.thercracer.com/2016/03/a-guide-for-setting-up-anti-roll-bars.html
One of the questions I get asked a lot is how to set-up Anti roll bars (Or Sway bars / Stabiliser bars etc), so I thought I would just make a guide on how I do it.
What is the big deal with Anti-Roll bars?
Anti-Roll Bars are an important tuning aid. They do not affect how the suspension works until you enter a corner. They tie the left and right suspension, either front or rear together to help control how the body rolls.So for example if a car turns to the right around a corner, the inertia will force the car to roll on its left side. If there is no Roll bar then the inner right wheel will raise up as the car rolls and you will find it hard to maintain grip as the car becomes unstable.
With a roll bar added the car will have the same forces as before as it tries to roll into a corner. The suspension will compress but instead of the right side wheel lifting up and making the car unstable, the sway bar starts to pull the right wheel up. This reduces the body roll, lowers the centre of gravity and ensures that the car is much more stable around the corner.
One of the other main benefits of sway bars is that you can actually have the suspension a little softer to ensure that you can move weight around to the rear on acceleration etc. The Sway bars cut in and give you the stiffness when you need it.
So if you want to ensure you are cornering like a champion, you want to ensure your roll bars are set-up well.
Eliminate the play
First get your anti-roll bar.I use the Tamiya 42295 Stabilizer Stopper |
As I use the TRF419 I fit the end mounts, and I also fit the Tamiya 42295 Stabiliser stopper and then will centre it once it is mounted.
I use the High Precision Stabiliser mounts |
Now you need to check that the bar can move freely and nothing is binding. The bar should just fall under it's own weight when you lift it up and let it go.
The grub screw holds the bar up at this stage |
Unscrew it gently and watch it drop |
Setting the Lift
Now you want to fit the bars to the stabilizer links.Check your links are the same length when you initially mount them |
You now need to pop your car on a Set-up station (or a flat surface). Whilst you are here double check that your downstops (Droop settings) are the same on each of the arms, otherwise the next part will be a waste of time.
Now we want to measure that the roll bar will have the same amount of 'Lift' on both sides when the suspension compresses. It is important that the arms on both sides lift at the same time to ensure that the car handles the same on right and left corners.
The method I and others use is to lift an arm with the droop gauge whilst tapping the opposite arm on the droop screw.
slide the bar under until you can Tap the opposite arm |
If one arm lifts at a different time to the other, (i.e if one raises at 6 and the other at 6.6) You will need to adjust the length of the Stabilizer links to ensure that the arms lift at the same measurement on both sides.
Adjust the link lengths to ensure symmetrical lift |
- Shorten the link for the arm that raises first
- Lengthen the link on the side that raises later
All ready for the track. |
"If there is no Roll bar then the right wheel will loose grip as the car rolls, and the left wheel will become overloaded. Ultimately losing grip around the corner."
ReplyDeleteSorry - but that is complete nonsense. If there is no sway bar, you will have more chassis BUT but also MORE grip on that axle, because the load difference between inside and outside wheel is less.
So just replace the word "no" with "a" in your sentence and it becomes correct.
"With a roll bar added the car will roll as before the left of the car will again start to compress but now instead of the right side lifting up and loosing grip it starts to pull the right wheel up. This reduces the body roll, lowers the centre of gravity and ensures that the car is much more stable around the corner."
In the same sentence you're saying it rolls as before and it reduces body roll. This is unlogical and wrong.
What a sway bar on a cornering car does is only:
1) reduces chassis roll
2) therefore reduces camber changes of the wheels
3) increases L/R weight differences on the respective axle
4) therefore increases slip angle due to tire-nonlinearties
With due respect - obviously you have not understood the effect and working principle of a sway bar. This article is complete misinformation - please study first and then re-write the article.