Suspension lift - how and why
From FogWiki
Having raised the suspension of my late A LWB with a third-party kit by Calmini, I am often asked for further information. Perhaps this article will enlighten those interested.
Standard Vauxhall Frontera with standard suspension and tyres.
Contents |
Why do you want a suspension lift?
- It looks “cool”
- to gain additional ground clearance
- to fit bigger tyres and therefore gain additional ground clearance
- to gain additional axel articulation
Quick fix 1 (Ride height)
The Frontera is now getting on a bit in age and it is possible that the front suspension has “sagged” (especially if you have fitted an aftermarket bull bar).
The Haynes Manual describes how to check and reset the front ride height – my 2.8TDI had sagged 30mm over 10 years !
Cost: £0 DIY
Quick fix 2 (Tyres)
The lowest point of the Frontera is the rear differential casing, and no matter what you do to the suspension, the diff casing will still be the lowest point. A quick way of getting an additional clearance of ¾” is to fit larger tyres.
The diameter of a standard set of Frontera tyres is about 29½”. The biggest diameter tyres you can fit to a Frontera without any other modification are 31x10½
Cost: from £60 per tyre
Quick fix 3
- Remove any side steps
- Remove tow bars (increases departure angle)
- Remove bull bar (increases approach angle)
- Remove front air damn below front bumper (increases approach angle)
All the above will remove protection of possible damage
Cost: £0
Standard suspension with 31x10½x15 “oversize” tyres on Vauxhall rims.
During the lifespan of the Frontera, the suspension went through three permutations:
- Early A up to mid 1995 (Leaf rear / torsion front)
- Late A up to late 1998 (Coil rear / torsion front – Isuzu)
- B (Coil rear / torsion front)
The Rear
The rear is reasonably easy to raise:
Early A leaf spring extended shackles will lift the early models between 1”-3” without any further modifications.
Late A and B coils can be replaced with stiffer versions (Note, the Late A and B coils are different – Late A are actually Isuzu Trooper, B’s are Vauxhall)
The rear can be lifted up to 3” with no further modification with the exception of the brake bias valve and brake union on the axel – these need to be lifted the same amount as your lift. The axel breather might need to be extended.
Cost: (search FronteraOwners or eBay for extended shackles), Coils from £60 per pair.
Note: if you were to raise the rear by 3", the panhard rod would move the axel approx 15mm towards the driver side. A drop bracket needs to be fitted to bring the axel back to the centr line of the vehicle.
The Front
Being “independent”, the front suspension of all the range of Fronteras is limited in what can be achieved.
The front torsion bar can be “wound up” to achieve about 1” of additional lift, any more would begin to seriously affect the steering geometry in that the camber angle would become too severe and would result in undue tyre wear. Even so, if you do increase the front suspension ride height, get your camber angle checked and adjusted as soon as possible.
It has been suggested that “flipping the ball joint” will bring the camber angle back into alignment. This modification is not recommended as the ball joint/upper arm connection is not designed to work with the suspension forces in this manner. The connection has been designed, tested and proven for a number of years and flipping the ball joint can only be detrimental to you and your passengers safety. DO NOT FLIP THE BALL JOINTS.
The camber angle is adjusted by way of adding or removing shims at the upper control arm mounting
Cost: £0 DIY + camber angle check
Lift Kits
The only manufacturer of suspension lift kits known to me is Calmini (http://www.calmini.com), although they only now do a kit for the B series.
My Late A series was lifted as follows:
- Calmini Frontera front upper arms, relocated droop stops and bracketry (modified)
- Calmini Isuzu Trooper +2” coils
- Calmini extended bump stops
- Calmini miscellaneous bracketry
- Calmini shock absorbers
- Calmini Panhard rod relocation bracket (modified)
Cost: £1000+ incl labour (might be DIYable if you have use of a good workshop with air tools etc)
3” Calmini lift with oversize 31x10½ tyres
Articulation
Now we have raised our suspension we now have the option of increasing it’s articulation.
When lifted, the suspension is limited in its downward travel by the droop stops at the front and the shocks at the rear. Fitting longer travel shock absorbers will allow the suspension to articulate more thus hopefully allowing the tyres to remain in contact with the ground, therefore giving drive, when otherwise your wheel would be hanging in the air.
Warning:
- Ensure the rear coils are adequately fixed to the axel as under extreme articulation they will dislocate and if not fixed, will fall out !!!
- Ensure that the suspension travel is limited by the shock absorbers and not the hydraulic brake lines.
At the limit of rear articulation with nearside rear coil dislocated
With a 3” suspension lift, it is theoretically possible to fit 33” tyres (but would they foul the wheel arches in extreme articulation ?
Other things to concider:
- Road handling will be adversly affected (having a higher centre of gravity)
- Inform you insurance company
Lawrence
