Over the last couple of weeks we’ve been installing our front and rear roll centre correction kits in all the cars in the Honed fleet. This is a unique product on the market so the install process will be unfamiliar to most, so we’ll go through it in detail below. Here’s what’s included in the basic front and rear kit:
In addition to your typical hand tools you’ll need the following:
- External circlip pliers
- Hydraulic press
- Suitable pieces of tubing to press the ball joint in and out
- Hammer
- A 4″ or 5″ (100 or 125mm) angle grinder with cutting wheel and flap disc. Alternatively any tool that will cut through a 10mm steel nut is suitable.
- Paint – To re-paint bare metal to prevent rust
- A drill and 10mm drill bit
Optional stuff that will make the install easier:
- Hydraulic gear puller – To remove the rear hubs
- Die grinder
Rear roll centre correction bracket
Starting off with the rear trailing arms. With the arms off the car it’s easiest if you remove the hubs and the dust shields for access to the lower part of the trailing arm. With those out of the way it’s simply a matter of getting to work with the grinder, slicing between the offending nut (indicated with the red arrow below) and trailing arm:
If you’re lucky the nut will come off easily as in this case, but in any case it’s a 5 minute job:
Then it’s just a matter of cleaning up the bare metal area with the die grinder, and touching it up with a bit of paint. To allow the bracket to fit correctly a small area of the bottom of the trailing arm that must be ground down, shaded red below.
With that area ground back we’re ready to fit the bracket. The bracket must be installed so that the inboard edge is parallel with the hub/brake caliper mounting flange, illustrated in the pic below with the red lines:
With it lined up correctly we temporarily install the two lower bolts in the bracket to hold it in place, and drill the extra hole required.
With that done the bracket is ready for the final installation and the 3 M10 bolts can be torqued to spec. The lower of the two caliper mounting bolts must be inserted in its matching hole before fitting the last bolt:
Then it’s simply a matter of reinstalling the trailing arms in the car following the manual for your car, using the provided M10x90mm bolt in place of the original outer lower control arm bolt. The ride height will also need adjustment. We found that raising your spring perches 18mm (3/4″) will correctly compensate for the new lower control arm angle.
Front roll centre correction ball joint
Moving on to the front, with the knuckles off the car firstly we removed the dust shield to get better access to the ball joint. This step isn’t essential, but we removed them to give better brake cooling with our air guides in place.
With that out of the way it’s simply a matter of replacing the lower ball joints with the Honed roll centre correcting items. Remove the ball joint boot and the circlip that retains the ball joint. With the circlip removed the easiest way to remove the ball joint is to situate the knuckle on the nearest firm surface or in a bench vice, and hammer away on the main body of the ball joint with a suitable piece of tube.
Check the ball joint bore for damage and ensure they are clean and dry. Then fit the Honed ball joint into the bore and push into place using a hydraulic press:
Once the ball joint is in place we then fit the support collar, firstly removing the ball joint boot to avoid damaging it, then tapping the sleeve into place with a deadblow hammer and piece of tubing. With the sleeve in place the retaining circlip is fitted and the ball joint boot re-fitted.
The roll centre correcting ball joint installation is now complete and it’s time to reinstall the knuckles in the car. Due to the revised geometry the ride height at the front will require adjustment, to achieve the same ride height as before the installation we raised the front perches approx 10mm or 3/8″.
Done. All that remains is to perform a wheel alignment. Check out the roll centre correction kits and our full geometry kit here: https://honeddevelopments.com/product-category/roll-centre-correction-kits/