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A well set up car will out perform a mega quick engine any day. Look at it this way - how many straights are there on your track and how many corners are there that you could make up time on? Below I am going to give a brief intro into car geometry, this is just an explanation about what the angles are and what they do, I will go into more depth later about what affects they have on car handling

Camber Angle

  Camber angle is the angle of the wheel when viewed from the front or rear of the car. There are three possible angles, positive camber, neutral camber and negative camber. If the top of the wheel leans into the centre of the car you have negative camber. If the wheel is vertical you have neutral or no camber and if the wheel leans out you have positive.

Neutral or no Camber Negative camber.

  Imagine you are driving your full size car round a fast right-hand corner, the body rolls to the left. The same happens to the wheel, If there is no camber on the wheel the top of the left wheels will lean out and you will end up running on the outside rim of the tyre. To counteract this we put negative camber on our wheels. This allows the wheel to tip over in corners but still maintains full tyre surface contact on the track giving maximum grip on corners.
The camber is adjusted by lengthening or shortening the top wishbone (usually the top but if it is at max adjustment then adjust the bottom).
A good starting point is 2 degrees negative on the rear and ½ to 1 degree negative on the front.

Toe-in & Toe-out

  These angles are the direction the wheels are pointing when looking at the car from above

Neutral Toe Toe out Toe In
neutral toe setting toe in setting toe out setting

  The above pictures show the toe angles on the front wheels only but the same rules apply to the rear wheels.
I am not going to explain in any depth why we have these angles as this will be covered in later articles. What I will say is that on a rear wheel drive car the front wheels will have neutral toe or toe-out. The rear wheels will have neutral toe or toe-in.

  With the correct toe angle on the front you will have a stable car that has good front end grip.
The correct toe angle on the rear will give good rear end traction through corners.

  The front end toe angle is adjusted on the steering links or track rods as they are called on a full size car. Shorten the links – more toe-out, lengthen the links –less toe-out.
  There are different methods to adjust the rear toe angle depending on which make and model of car you drive, almost all adjust the rear lower wishbone to give desired angle.

  To measure the toe angle is not easy, one method is to use the camber gauge. If you want 1 degree toe-in set your wheels up with one degree of negative camber. Take a measurement from the top centre of the inside rim on the left wheel to the top centre inside rim of the right wheel. Do the same for bottom centre inside rim on both wheels. Transfer these measurements so that the distance top centre is the same as front centre on the inside of the rim, this sounds complicated but when you try it it’s not that bad. Another way of putting it is measure at 12 o’ clock and 6 o’ clock and transfer to 3 o’clock and 9 o’ clock.

  Start settings are 2 degrees toe in at the rear and 1 degree toe-out at the front.

Caster Angle

  The purpose of caster angle is basically to allow the front wheels to self-centre. Imagine the wheels on a good shopping trolley (if you can find one), if you look at the wheels the spindle of the wheel is not directly below the mount but trailed back at an angle, this is the caster angle. When you push the trolley the wheels all point in the direction of motion so are self-centred.

  All rear wheel drive cars have positive caster on the front wheels.

Neutral Caster  Positive Caster 
neutral caster rc setup guide positive caster rc setup guide

  Although the main reason for the caster angle is to self-centre the wheels the angle can affect the car handling as well. Too much caster and you can get what is known as wheel shimmy. This is when the front wheels flick side to side rapidly .Too little caster can make the car oversteer and be a little nervous. The caster angle is adjusted by sliding the front wishbones on the hinge pins. To increase caster slide the top wishbone back or the bottom one forward or a bit of both, and do the opposite to reduce the caster. It is very difficult to measure caster angle so it is more a case of trial and error to get the correct setting.

  The best starting point would be both wishbones in the centre of the hinge pins as there is positive caster built into the steering hubs.

Ride Height

  Just a quick one on the car ride height. Try to run the car as low to the ground as you can without the chassis scraping the ground. Ride height is adjusted on the collars of the shocks, screw them down increases the ride height and visa-versa. Set the rear end a couple of millimetres higher than the front.

This is just the basic car set-up and will get your car round the track. Next we will go into more depth and detail about different changes.
If you wish to alter the settings only change one at a time to see if there is an improvement, don’t change two or three at a time as you will not know what has worked and what hasn’t.

Always remember, there is no such thing as a perfectly set up car. There is always a compromise, give to the front and you loose from the rear, give to the rear and you loose from the front.

Finally , the best set-up in the world will not handle if you do not have the correct tyre choice. If you don’t have the right rubber on the car will not handle. If you are stuck ask the other drivers what is working.

(Pictures and information supplied by Steven Robertson )

To elaborate a little on the previous tip

Often overlooked and underestimated. The ride height of your car will determine a few things. Firstly and most importantly it will affect the centre of gravity of your car. The higher the ride height, the higher the centre of gravity. This will affect your cars ability to corner.

Let me explain: The centre of gravity of your car is basically where the centre mass of the car is, front to rear, side to side and height above the ground. All these factors will converge at one point on you car to determine the car’s centre of gravity. Apart from moving fuel tanks and battery packs we are limited to the amount of changes we can make to the linear centre of gravity. What we can do is affect the lateral centre of gravity.

When your car is travelling full speed up the straight it wants to keep travelling in a straight line. When we get to the end of the straight we want to turn the corner but the car still wants to keep going straight on. Now we have to think about leverage, the longer the lever, the more leverage. If your lever is 25mm long and you double it to 50mm then you double the amount of force applied. Now to apply it to the cars, if you run with 20mm ride height then drop to 10mm ride height you will have half the amount of force trying to push you in a straight line so it will let you turn the corner easier and quicker.

The front of the car should be a bit lower than the rear to allow for weight transfer during braking and cornering.

Run the minimum ride height that the track conditions will allow to prevent the chassis from Scraping the ground at every corner.

A good starting point is front-6-10mm and 8-14mm rear.

Droop is determined by the amount that the chassis can lift from normal ride height until the wheels lift off the ground.

When the car turns a corner most of the weight of the car is transferred to the outside wheels. If we had a fixed axle front and rear, the inside wheels would lift. But because our cars have independent suspension we can compensate for this. By giving our cars droop we allow the springs to exert pressure onto the inside wheels give us more traction at the front, reducing under steer. And increasing traction at the rear, preventing spin out and diff-out.

The droop is adjusted at the front by adjusting the screws on the lower wishbone. Screw out the screw-more droop. Screw in the screw-less droop.

On the rear this is usually adjusted on the top wishbone, screw in the screw –less droop. Screw out the screw-less droop. Remember, too much of something can be as bad as too little.

To start with, 3-6mm front. 4-8mm rear shouldn’t be far away.

The dampers fitted to your car are there to ensure that the tyre remains in contact with the track at all times. The springs are fitted to support the weight of the car and prevent the chassis from scraping the ground.

That’s the basics, now for a bit of fine-tuning.

I am talking about oil filled dampers here. No matter what spring rate the springs are, the oil in the shocks must be the right viscosity to counteract the spring oscillation but still allow the piston to travel through the oil. In other words it stops the car bouncing up the track but still allows the car to soak up the bumps.

The shock oil is graded in numbers, the lowest number being the thinnest oil and visa-versa. Different manufacturers have different number systems so pick a brand and stick with that one brand throughout so you have a common reference.

To be precise you must ensure that all the wishbones are free to move and none of the hinge pins are bent. Remove your shocks and wheels and put the chassis on a block to clear the surface. Disconnect any anti-roll bars. The wishbones should lift and drop with no tight spots or resistance. If there is any, solve the problem before testing the shocks. Now re-fit the shocks and wheels and put the car on the flat surface.

To get the car to its normal ride height you must push down and lift the chassis a couple of times finishing with a push on the chassis. Release the chassis and let it rise on its own. Now without pressing on the chassis, roll the car back and forth about a car length. This will ensure the tyres don’t have a grip on the worktop.

You must do this every time you test the shocks.

Now, to test the rear spring/oil balance, push the rear of the chassis down to the stop and release. Note how the chassis returns to its ride height. If the car springs back straight away then the oil is too thin. If the car starts to rise and stops then the oil is too thick.

What you want is the car to rise up to its normal ride height under the control of the dampers.

If you don’t know what oil is in the shocks to start with have a starting point. This depends on the spring rate, if it’s a soft spring start with thinner oil and the same with stiffer spring use thicker oil.

You may have to buy 2 or 3 bottles of oil for both front and rear to get the exact oil/spring balance but it is well worth a few pounds to get it right. And the oil you don’t use can be used if you change springs or do a bit of tweaking to suit track conditions which I will cover later.

If you want a bit of a reference try it on your full size car, push it down and release and you will see it slowly returns to its ride height.

Now we have covered the balance between the oil and springs I will just say a bit on the springs themselves.

In general the springs on the front should be stiffer than the springs on the rear.

This may confuse some people as a lot of cars come from the factory with stiffer springs on the front or the same on both. To simplify matters, the softer the spring the more grip. So to get the drive to the rear wheels we tend to put a softer spring on the rear, within reason. 1 or 2 spring ratings of a difference is enough. As long as you have the oil matching the spring you can balance the car with toe-in, camber etc.

Always remember, car set up is a compromise. What you gain at the front you loose at the rear and what you gain at the rear you loose at the front.

I have gone on a bit about spring/oil balance but it is essential that whatever springs you have the oil in the shocks should match them.

Just a quick note, if you have some fancy pistons fitted, the set up is the same; the oil still has to match the spring.

If you have anti-roll bars fitted follow these simple rules
  • Wet track-disconnect or soften as much as possible.
  • Damp or slippy track-soft as possible
  • Grippy track-stiff as possible.
This is a guideline and will be elaborated on in later articles.

In 1/10 scale racing there are many choices the racer has to make; on-road or off-road, battery power or nitro power.

Here at CRCC we favour nitro on-road (touring cars) and are lucky enough to have the facilities to cater for it! Having said that, 1/10 electric cars are most welcome to come along and race at the track as well.

When the club started, 1/10 scale on road was the car of choice at the club, however many club members then progressed onto bigger things, namely the 1/5 scale cars!

Our track caters for both 1/5 and 1/10 scale cars, however the 1/10 scale cars run a shorter circuit than the 1/5 cars.  This is for two main reasons – to reduce the strain (time spent at high revs) on the 1/10 scale engines by reducing the length of the main straight and also to allow the cars to complete more laps per race (and between re-fuelling!) – a typical nitro qualifying round being 5 minutes (about a tank of fuel) compared to 10 minutes for the 1/5 scale.  The nitro final is generally a 10 minute race requiring the services of a “pit-man” to do the all-important re-fuelling job!

The 1/10 scale cars come in many guises nowadays from the user-friendly “Ready to Run” (RTR) versions through to top spec race kits.  Starting prices for an RTR version can be as little as £250.

The cars may be small but the specifications certainly aren’t! Even the entry level RTR versions allow a decent amount adjustments to tailor the car to the track and driving style, with many after-market upgrades, (or hop-ups), available to give the driver more opportunities to change the cars set-up to suit the track conditions or simply to make the car look better!

The 1/10 scale nitro cars are typically 4 wheel drive machines (compared to the 2 wheel (rear) drive of the 1/5) using either fibre belts or a shaft to provide the link between front and rear wheels.  The choice between belt-drive or shaft-drive is usually purely a personal decision.  The cars also feature a differential, or diff, at both the front wheels and the rear wheels, which in many cases, is adjustable to provide yet more tuning options!

Motive power is provided by a single cylinder nitro engine running on a methanol based fuel.  This fuel comes in various grades based on how much methanol is in the fuel – the more methanol, the more power will be developed.  The fuel also carries lubrication in the form of oil which also helps with keeping the engine cool.

Many cars now come standard with a two speed centrifugal gears capable of propelling these cars up to 55-60 mph depending on the gearing and track conditions!  One of the newest cars on the market can now come with a three-speed gearing, capable of going on to 80mph!

Of course having all this power means you must have some way to stop it!  The 1/10 scale cars typically use 1 or 2 disk brakes either on the main shaft of a shaft-driven car or on the layshaft of a belt-driven car.  These disks can be simple glassfibre disks through to vented steel brake discs, or on a few of the top spec cars, bonded brake pad material as used on full scale race cars!

One of the most important areas of the car is its suspension.  A car with poorly set up suspension will be difficult to drive and almost impossible to race with!  Most car kits come with oil-filled, coil-over suspension sets which are completely adjustable from the viscosity of the oil used in the dampers to the stiffness of the springs used in the coil-over.  Those cars that do not come with this technology can very easily be upgraded to have them.

The other most important area of car set-up, in fact many would argue the most important area, is tyre choice.  Since it is the tyre that is the only part of the car that is in contact with the track, the correct choice of tyre is vital.

Tyres come in many guises. Firstly the material; the racer has the choice of either rubber or foam tyres.  Rubber tyres are then separated into two categories, traction rubber and temperature rubber.

Traction rubber tyres rely on the softness of the tyre and its adhesive properties to provide the “stick”.  Most traction tyres are sold as “long lasting” or “high wear” tyres and are excellent for racers on a budget who don’t want to spend a fortune on tyres.

Temperature tyres rely on a heat build up in the tyre to soften the tyre and provide the grip.  This heat is generated by the friction of the tyre on the track and also by the amount of heat in the track already.  Depending on track conditions on the day, it may be necessary to change your tyres several times during a race meet to get the best from the conditions!

Just when you thought things weren’t complicated enough, rubber tyres also require an “insert” is used.  The insert provides the “firmness” of the tyre and just like the tyre themselves, the insert comes in many variations from soft to hard!

Foam tyres don’t require inserts as the whole tyre is a solid foam unit, glued onto a rim.  The foam tyre is based on its “hardness” also known as its shore.  Typical foam tyre shore ratings are in the 30-60 shore range (the higher the shore rating, the harder the foam).  Foam tyres can provide incredible grip but have a tendency to loose their “trueness”, that is the tyre wears unevenly depending on your suspension set-up.  The tyres can be “trued” using a special piece of equipment, but these machines can be expensive.

Of course, choosing the tyre type and insert is also about judging the surface that you are running on, so as you can see, tyre choice (and insert) can be rather complex!  Best policy is to go along to the race track and ask what the locals are running and start from there!

One of the great things about 1/10 scale cars is the choice of body styles that are available.  Practically every type of touring car shell is available from the BTCC and the German DTM series as well as the more exotic body shells from GT style racing through to standard “street” style and rally!  Most of these body shells are available at under £20 each (unpainted) and are made from a tough wearing lexan material which is capable of taking a reasonable amount of abuse!

Tempted?   Come down to the track and meet us!

"Thank you Ross for the information"


Engine: Novarossie TOP TT12/T, Pipe: RD Logics Turbo Outlaw, Fuel: Tornado 16%, Gearing: Standard Kit, Servos: Steering: Hitec HS5925MN, Throttle/Brake: Hitec HS5625MG,

Modifications to the car

K-Factory Low Profile Fuel Tank

RD Logics Turbo Outlaw Exhaust Pipe.

K-Factory Carbon Fibre Radio Tray and Side Brace.

K Factory Aluminium /  Carbon Fibre Shock Mounts front and rear.

(Pictures and information supplied by Ross Cumming )

Copyright © Ross Cumming.