Raising Car’s Ground Clearance: Raising the ground clearance of vehicles is done with the aid of locally fabricated metallic plates called spacers. The spacers are fitted between the shock absorber mountings or springs and the vehicle chassis to improve the vehicle’s ground clearance. In the case of special purpose off road vehicles, raising the vehicle ground clearance with spacers involves replacement of the springs and some suspension components to adapt to the height conversion.
Let us take a Toyota Premio. Raising your Premio saloon car by fitting the common locally fabricated one to two inch metallic spring spacers is technically not recommended due to the potential damage it may cause to your car suspension as well as compromise your safety when the car is raised above its dynamic safety limits.
Whereas raising your Premio with spacers would provide an immediate solution to ground clearance challenges, the long run damage to your car suspension, altering ride handling quality and potential risk of causing an accident while driving fast on the highway ought to make you think twice before you make this decision. Fitting spacers damages suspension components after a while. This happens when the upward travel of the suspension struts do not compress fully upwards yet the lower suspension arm continues to move.
Damage to upper suspension often breaks the lower strut shaft as well as the bushings, ball joints and CV joints. Fitting spacers to your Premio may make it high and unstable.
The suspension design of your car is calibrated to work with its original ground clearance to ensure that you can drive safely at low or high speeds when maneuvering around sharp bends. Altering the height of the car will affect the tolerance or limits of the above design and may lead to accidents due to loss of dynamic stability when driving on uneven roads or through sharp bends. You can safely raise the car slightly by replacing your tyres with a size recommended by your car manufacturer (usually indicated on the driver side door B pillar) or carefully worked out by calculating a new tyre aspect ratio. Tyre dealers can help you determine the right tyre size for this purpose.
But what if you have decided you must raise your ground?
How to raise your car for ground clearance:
It is essential to know that almost all these measures of increasing the ground clearance will affect other driving dynamics. So these are advisable only if you are in desperate need of higher ground clearance.
Spacers under the coil spring or longer coil springs
The spacer is a rubber pad about an inch thick which sits under the coil springs. One way to increase the ground clearance of your car is to use spacers under the coil spring. This will affect the overall handling and driving as the angle of the lower arms and links will change, and ride will become stiffer. The price of these spacers will vary from car to car but these aren’t very expensive.
The easiest way to get better ground clearance is to get a bigger set of tyres. So for example if your stock tyres are 185/60 R14, you can opt for 185/65 R14 or if your car permits you can get 185/70 R14 or 195/65 R14 tyres. If you want you could get larger rims (15-inch instead of 14-inch), and upsize the tyre. But keep in mind that increasing the overall diameter of the tyre will adversely affect your odometer readings (it will read too slow for a given speed), you will get poor acceleration and it can affect handling too. Go this route only if you are desperate for ground clearance.
Re-cambering the springs
Re-cambering is essentially bending the leaf spring to a more acute angle to raise the ground clearance. This applies to older vehicles that have a leaf spring suspension. If you have a leaf spring suspension setup on your car you can get the leaf springs re-cambered. This will give you more ground clearance but also remember that this will have a negative impact on the way the car drives. It will reduce overall ride comfort and make the ride more “jumpy”, as well as raising the center of gravity of the car.
Adding extra leaf in leaf spring blade
This again is a way to improve the ground clearance of your car, especially useful for vehicles like the Maruti Omni or Gypsy, or older Mahindra Boleros and Scorpios (first generation). You can simply add another leaf spring blade to your leaf spring pack to improve the ground clearance. This method too will make the ride more stiff and unsettled.
Spring over axle setup
This is a major modification to increase ground clearance in vehicles like the Maruti Gypsy or Mahindra MM540 (predecessor to the Thar DI). Here the leaf-spring pack, instead of sitting under the axle, is modified to be placed over the axle, increasing ground clearance by quite a bit. But this modification puts pressure on the steering components and drive shafts.
For torsion bar suspension
If your vehicle has a torsion bar suspension you can get it adjusted. These are usually adjustable and can be used to increase ground clearance by a small margin. This won’t affect ride quality too much, depending on the level of adjustment.