www.106owners.co.uk
To adjust the torsion bar on a Peugeot 106, first, lift the vehicle and secure it on jack stands. Then, remove the rear axle mounting bolts and lower the axle slightly to access the torsion bar adjustment. Use a torsion bar adjustment tool or a proper wrench to turn the adjuster bolt, which will either raise or lower the rear suspension. Finally, reassemble all components, double-check the alignment, and ensure the vehicle is at the desired ride height.
It has macpherson struts in the front and torsion springs at the rear.
as the rear is torsion it is not straight forward. the torsion bars have to be removed one side at a time, with the torsion bar out simply adjust hub the required amount and replace torsion bar. then do the other side. this can be hard as the bars can be difficult to remove. best left to professional should cost between £60-£100
Front is torsion bar and rear is leaf spring. Both front and rear have anti-sway bars http://en.wikipedia.org/wiki/RPO_ZR2
The 1964 GMC does not use torsion bars, in 4x4 applications it uses a leaf spring in the front. The 2wd uses coil springs. Both models use leaf springs in the rear, the Chevy version used what is called a truck arm suspension with coils in the rear.
Try the Haynes Manual.
A Vauxhall Vectra rear suspension diagram is available through their service manual. Online Vectra service manuals are also available to be purchased through several websites.
To raise the torsion bar ride height on a Peugeot 106, you'll need to adjust the torsion bars themselves. Start by safely lifting the rear of the vehicle and removing the rear wheels. Then, access the torsion bar adjustment bolts located on the trailing arms and use a suitable tool to rotate the adjusters. Typically, turning the adjuster clockwise will raise the ride height, so make small adjustments and check the height frequently until you achieve the desired level.
To adjust the rear torsion bars and prevent the rearend from sagging, first, locate the adjustment bolts on the torsion bar crossmember. Using a wrench, turn the bolts clockwise to increase the tension on the torsion bars, which raises the rear suspension height. Make small adjustments, checking the height after each turn to ensure you achieve the desired ride height without over-tightening. It's advisable to have the vehicle on level ground and consider the overall suspension geometry during adjustments.
The Peugeot 306 has a conventional Mcpherson strut front end with coil springs over shocks. The rear end is a solid axle with torsion bars that run across the car linking both arms. There are no rear coil spings.
In the manual, look in library
Revised leaf springs in the rear. Revised torsion bars and torsion bar cams (a.k.a. 'pork chops') in the front