Toyota MX83 Cressida Roll Centre Adjusters

Toyota MX83 Cressida front control arm roll centre adjusters.

When lowering a vehicle you will find that in most cases your roll centre is going to be affected, but you are probably unsure of what exactly it is that changes, so let us briefly explain below.

Take the diagram below as an example - on the very left you have the stock height of a vehicle, and where the control arm meets the bottom of the strut is a ball joint that is connected to a steering knuckle (not shown in this picture).

It shows that the ball joint and the control arm both sit at 0 deg (horizontal) under loaded weight of the vehicle, this is not entirely accurate and most vehicles will sit with a control arm of 5 - 7 deg declined. This is how it should remain to retain correct roll centre on the vehicle. Note that it is not uncommon for control arms to have a ball joint curvature of roughly 5-9 degrees for correct installation angle into the steering knuckle.

When the vehicle is lowered it will consequently raise the ball joint & lower control arm and therefore affects the roll centre of the vehicle, which can be seen in the second diagram, and it is now sitting between 10-15 degrees.

To put it simply this changes the height of your roll centre, which is an imaginary point of which the vehicle rolls over. The most detrimental consequence of this is that it changes your handling characteristics and can induce bump steer, increased tyre wear, and excess camber.

By installing RCA's (roll centre adjusters) you will see that this corrects the issue. The RCA spaces the control arm from the bottom of your suspension strut / knuckle, lowering the ball joint / control arm down past 0 deg to around 5 - 7 deg declined (diagram is not accurate).

This is a very brief diagram to show simple functionality of this product, a lot of applications will have a ball joint setup into a steering knuckle, McPherson strut being the most common.

For more information on vehicle roll centre please click here

Standard height Roll Centre

Lowered

Corrected with RCA

What are the benefits?

• Reduce bump steer on lowered vehicles
• Corrects control arm ball joint characteristics
• Restores original steering geometry

Specifications -

• 40mm height
• Large alignment ring, less likely to shear or have misalignment issues, compared to other RCA's on the market
• Solid milled alignment sleeves
• High tensile bolts and lock washers

Qty -

• 1 Pair of Toyota MX83 Cressida RCA's