Welcome to my Cobra Replica build blog.
Please contact me if you would like to know more detail as i progress."CR3514@live.com.au"

Saturday, January 14, 2012

Steering Rack Tie Rods

The CR chassis has been jigged up to accept the VP commodore steering rack.
I purchased a reconditioned Power Steering Rack which came with new Tie Rods, but no Tie Rod end ball joints. A quick email to and fro with Classic Revival advised that VP Tie Rod Ends should be fitted.

The Steering Rack fitment to the chassis is accurate, no mods neccessary.

When test fitting the rack however, I found that the VP Tie Rod Ends didnt fit the VZ Knuckles properly.
The issue is the Rack End Ball Joint stud is too big in diameter to fit the small VZ Knuckle taper and seats only partially through the Knuckle Steering Arm.

Steering Rack as delivered, no Tie Rod Ends fitted.

VP Tie Rod End doesnt fit far enough into the VZ Knuckle Steering Arm.

The taper is the correct degree, but too large in diameter.

The next step was to go and purchase VZ Tie Rod Ends, These fitted the VZ Knuckle perfectly, but didnt screw on to the Tie Rods.
The VP Tie Rod Ends are 14mmx2mm pitch  thread, the VZ is 16mmx2mm.
At this point I reverted to the ball joint and tie rod end bible, The Roadsafe Suspension Catalogue, can be found online at:

I could not find a Tie Rod End with 14x2mm female thread and small diameter 10degree stud, so after comparing VZ and VP Tie Rods at the local parts store, I purchased VZ Tie Rods to retro fit to the VP rack, the inner joint is identical, but the rod needs shortening by 20mm, an easy task.

Remove the lock nut from the Tie Rod.
Cut the boot zip ties and remove the boot from the rack.

Bend back the locking tab, a new tab is supplied with the New Tie Rod.
Un-screw the ball joint housing from the Steering Rack End.
There are flats on the Ball Joint Housing for a spanner.

Tie Rod removed.

The original VP Tie Rod length is 305mm
The original VZ Tie Rod length is 325mm
Shorten the VZ Tie Rod by 20mm, I used an angle grinder with thin cut off blade, then chamfered the end with file.
Extend the thread length by 20mm with 16mmx2mm Die Nut so the VZ Tie Rod Ends can screw on far enough with adjustment room for Toe in and Lock Nut.

The extended thread will run over the top of the machined adjustment flats on the Tie Rod.

Screw the Tie Rod back on to the Rack End, use some some Anti Seize on threads.

Fold over the locking tab.

Slide on the Boot Cover, fix with new Zip Ties.

Refit Lock Nut and Tie Rod End.

Finished, .....almost.

I didnt like the thread sticking out past the Lock Nut, so I've machined up some tapered covers and brazed them to the nut to smoothen the look.

To adjust the toe in/out, i undo the lock nut revealing the flats on the Tie Rod Shaft, adjust by turning the Tie Rod Shaft, then re-tighten the Lock Nut.