Setup Guide

The aim is to set the car up with just enough grip so that it doesn’t spin out or understeer, but with no extra grip. Excess grip wastes battery power and (even with a stock motor) slows the car down.

Adjustments should be done one at a time so that you can feel for yourself exactly what affect it has: if you do two at once, they might cancel each other out providing no improvement.

All adjustments should be done in small increments: half a degree change in camber or toe-in, one spring rate different, 5wt oil different and so on.

Try to keep the difference between the front and rear set-up at a minimum. Big differences in spring rate, ride height, shock oil and so on offer no advantage. If your car has major oversteer or understeer, then there is most likely a problem with the car, such as a bent hingepin or a binding wishbone or driveshaft. No amount of set-up work will get around this problem.

Setting	Explanation	Affect	Starting Point	Min	Max
Tyres	Tyres easily have the biggest	Softer: More grip and more steering,	Soft tyres will be damaged if used in too
	affect on the handling of the car.	but less duration and shorter tyre life.	hotter conditions, so start on a harder
	They are the only part of the	Use in colder conditions.	compound. Then, if the car has an overall
	car touching the track, so if	Harder: Less grip and less steering,	lack of grip, use a softer compound.
	they’re wrong, the rest of the	but more duration and longer tyre	If the car oversteers, or if the tyres ‘grain’,
	set-up is irrelevant.	life. Use in hotter conditions.	use a harder compound.
		Always use the same compound front	Only use treaded tyres when the track is at
		and rear.	least 60% damp. Using them when it is
			any dryer will quickly wear them out. Use
			a soft slick instead.
Shock	Shock springs and oil control	Softer Springs and/or Thinner Oil:	Start off on equal springs and oil all round
Springs	the body roll and damping of	More grip, but more body roll,	(try a medium spring and 40-50wt oil).
and Oil	the car. Oil and springs should	slowing down the car’s ability to	Don’t run more than one spring rate
	usually be adjusted together (if	change direction.	different front to rear (i.e. don’t run one
	you stiffen the springs, thicken	Harder Springs and/or Thicker	end very soft and the other very hard).
	the oil). However, oil can be	Oil: Car corners flatter, but has less	Too bigger difference front to rear can
	changed on it’s own by 5-10wt	grip. Also puts more pressure on the	cause bad oversteer. Use thinner oil at one
	to change the front to rear	tyres, making them squeal or scrub.	end only to increase the grip at that end
	balance.		(maximum difference 10wt).
Shock	Shock pistons can be used in	Use more/bigger holes and thicken	Start off on the kit pistons. If there are
Pistons	conjunction with oil to change	the oil to improve bump handling.	several choices in the kit, choose the
	how a car handles bumps (no	E.g. 60wt 3 hole corners the same as	medium pistons.
	on-road track is perfectly flat).	40wt 2 hole but handles bumps
		better. Going too far can make the car
		‘bounce’ though.
Ride	The distance between the	Lower: Better direction change, but	7mm front	6mm	10mm
Height	bottom of the chassis and the	chassis can ‘ground’ causing the car to	8mm rear
	ground. Ride height affects the	spin.
	overall handling of the car, and	Higher: Better handling of curbs and	It is normal to run the rear 1mm
	can also be used to change the	bumps. Less likely to ground, but	higher than the front, as there is more
	balance front to rear.	poorer direction change.	weight at the rear.
Droop	The maximum downward travel	More: Better bump handling but less	12mm	Ride height	15mm
	of the wishbones. Adjusted by	stable cornering.		4mm (i.e.
	unscrewing the shock rod-ends	Less: Poorer bump handling but		make sure
	or on wishbone grub-screws.	more stable cornering.		there is 4mm
	Can be measured by setting the	Make sure shock-lengths (or grub-		more droop
	car at maximum ride height	screw settings) are equal left to right.		than ride
	(put lots of shock packers in)			height).
Camber	The angle of the wheel in	More: More grip and stability, but	1.0deg	0.5deg	2.0deg
	relation to vertical (top of wheel	more tyre wear and more drag.
	leans inwards). Adjusted on the	Less: Less grip and stability, but	Increase the camber by ½-1deg at one end
	upper wishbone turnbuckle.	better tyre wear and less drag.	only to increase the grip at that end.
Castor	The angle of the front hubs in	More: Less steering into the corner	10deg	7deg	13deg
	relation to vertical (looking at	and more steering out of the corner.
	the car from the side). Adjusted	More stable in a straight line.
	by moving the front upper	Less: More steering into the corner
	wishbone or by fitting different	and less steering out of the corner.
	hub carriers and bulkheads.	Less stable.
Anti	The angle of the rear wishbones	More: More rear-end grip out of the	Level	Front of	Level
Squat	in relation to horizontal (looking	corner but less through the corner.		wishbone
	at the car from the side).	Less: Less rear-end grip out of the		3mm higher
	Adjusted by inserting spacers	corner but more through the corner.		than the
	under the front of the wishbone			back.
	hangers, or by fitting different
	hubs or wishbone hangers.
Rear	The angle of the rear wheels in	More: More rear-end grip, but causes	2 degrees	1 degree	3 degrees
toe-in	relation to parallel, (looking at	speed to be scrubbed off and
	the car from the top). Adjusted	increases tyre wear.
	on the lower rear turnbuckles or	Less: Less rear end grip, but more
	by fitting different hubs and	speed, duration and tyre life.
	wishbone hangers.
Front	The angle of the front wheels in	Toe-out: More steering into the	Parallel	1 degree	1 degree
toe-in /	relation to parallel (looking at	corner, but less stable.		toe-in	toe-out
toe-out	the car from the top). Toe-out is	Toe-in: Less steering into the corner
	when the wheels point	but more stable.
	outwards, toe-in is when they	Both scrub off speed and increase
	point inwards. Adjusted on the	tyre wear, so try to run the wheels
	front lower turnbuckles.	parallel.
Ackerman	The difference in turning angle	Less (longer centre rod): More	Kit setting	Kit – 2mm	Kit + 2mm
	between the inner and outer	turn-in but less steering through the
	front wheel. Adjusted on the	corner.
	centre turnbuckle (remember to	More (shorter centre rod): Less
	adjust the steering links to keep	stable and less turn-in but more
	the front tracking level).	steering through the corner.

Problem Solver

When your car has understeer or oversteer, follow these changes in the order given. Remember also to follow the rules given above (don’t use softer tyres if they are already scrubbing, don’t use harder front springs if the front is already harder than the rear and so on). If your car has both oversteer and understeer (at different points of the corner) try adjusting castor first. If you can’t cure the problem, try asking advice from someone who is going well with the same car as you.

UNDERSTEER				OVERSTEER
Tyres	Softer	1 compound		Tyres	Harder	1 compound
Rear Springs	Harder	1 spring		Rear Springs	Softer	1 spring
Front Springs	Softer	1 spring		Front Springs	Harder	1 spring
Rear toe-in	Less	1/2 degree		Rear toe-in	More	1/2 degree
Front Camber	More	1/2degree		Rear shock oil	oil	5wt
Front shock oil	Thinner	5wt		Rear Camber	Lengthen	1/2degree
Rear Camber	Less	1/2degree		Ackerman	Less	Lenghten rod
Front toe_out	More	1/2degree		Front toe_out	Less	Wheels parrallel
Ackerman	More	Shorten rod		Front Camber	Less	1/2degree