Page updated
February 2004
FAQs / Technical Hints - Ride Height and Droop
Definitions
Ride Height - The height of the car chassis above the ground.
Droop - The amount by which the chassis can be lifted before the wheels lose contact with the ground.
A delicate balance between scraping the ground and allowing the car to roll-over in corners. tips
Crucial to control the transfer of weight during cornering, braking and acceleration. tips
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Southend, the world's longest pleasure pier
Ride height
Setting the correct ride height is important for two reasons: -
- If ride height is too low, the car will scrape on the ground/track surface when cornering, accelerating/braking, or if the track surface is bumpy.
- If ride height is too high, the centre of gravity of the car will be too high, and the car will roll - and possibly turn over - during cornering.
On a flat surface, a ride height of 5mm at the front is a good starting point.
How to check/adjust the ride height
Use a ride height guage - normally a 'block' with stepped indentations at 1mm intervals - to measure the ride height at each end of the chassis and at the 'corners' between the wheels.
Depress the car at each end first to ensure that the shock absorbers are at 'rest'.
Ride height should be the same each side.
Adjust the ride height in accordance with the car's instruction manual - generally by adding spacers to the shock absorbers above the springs. CARE!: it may be necessary to adjust the length of the shock absorbers to maintain efficiency.
Remember! Foam tyres wear and become smaller with use - so check and adjust the ride height regularly for indoor racing.
Droop
Unrestricted droop allows the car to move freely at all four corners and the transfer of weight will be maximised.
That is not always a good thing however, because it can allow the car to 'flip' over during hard cornering, or 'see-saw' between manoeuvres.
How to check/adjust the droop
With the ride height set, push the height guage under each end of the chassis in turn - being careful to keep the guage central on the front/rear axis of the chassis.
At each 1mm 'step' check whether the wheels can turn. Adjust the droop screws so that both wheels start to turn at the same point. 3/4mm rear droop and 2/3mm front droop is a good starting point for flat surfaces.