In the next few weeks there will on here be basic set-ups for stock cars racing counter clock wise around tarmac tracks! We will start with caster..camber..and toe!  .

In the world of stock car set up's, the front end settings can become downright confusing. But there’s much to gain by understanding caster, camber and toe settings, and how they can work together to make your stock car corner quicker and be more stable on the straights.

Caster

Imagine a side view of the car that shows an imaginary line running through the center of the upper ball joint/rose joint to the center of the lower ball joint/rose joint. This is known as the pivot line. If this line is vertical, then the caster measurement is zero, or no caster. When the top of this line is leaned toward the rear of the car, then this is known to have positive caster.

Try pushing around a chair with casters on it. You will find it has no directional stability. This is because the casters have negative caster and want to follow the slightest force in any direction. So therefore your race car should have positive caster to achieve that directional feel.

As opposed to some years ago, some  race cars now have power steering. This allows the use of more caster.

In stock cars using stock wish bones and and uprights or near-stock frontend geometry, caster can easily  be increased from standard road type settings. Caster stagger is also a useful setting. Caster stagger occurs when there is more positive caster on the right side than on the left. When entering a turn to the left, the excess caster on the right will give the car a natural tendency to turn left.

Long tracks, especially the tarmac ones, need only a small amount of caster stagger—perhaps only 1 degree. At a ¼-mile oval, much more can be an advantage. I have seen some stock cars useing as much as 6 degrees of caster on the right and 4 degrees on the left. This is a lot, but the car turns in easily. These are however power steering units and without this you would need arms like "ARNIE".

Setting caster is easily done with a gauge built for that purpose. Most of the shop-bought units screw on or magnetize to the front hub. Turn plates are then placed under the front wheels. The wheels are steered a certain number of degrees each way. The gauge will then read the caster in degrees. This type of gauge may be necessary with aftermarket rod end type suspension.

Lots of caster stagger is ideal on a small tarmac tracks. Get all the caster the right side will allow with the correct amount of camber. Then adjust the left-side caster using enough caster stagger to give you the feel you want entering a turn. Start with a lot and then take it out if you don’t like it.

Camber

Another setting for the front suspension is camber. Camber is measured at the wheel not the ball joints. A frontal view of the car, when the wheel is straight up (no lean), shows the wheel has no camber. When the wheel is leaned in at the top toward the center of the car it has negative camber. Therefore, when it leans out at the top, the wheel has positive camber. Stock cars can use both positive and negative camber settings to their advantage.

Camber is a very visible part of the frontend settings. We have all seen the right front leaning toward the center of the car. Sometimes this is severe enough that the outside of the tread is not touching the ground. This much negative camber reduces the traction at the front of the car. If the car seems balanced in its handling with this set up then the suspension is crippled somewhere else.

Only the right amount of camber will net maximum traction. Selecting the right amount is determined by the built-in suspension design.  When the wheel goes up in relation to the chassis, which is called bump travel, the camber increases, or gains. Camber is designed to reduce the effect of tire flex. Camber gain also adjusts for suspension movement. Together, they work to keep the tread surface flat on the track. The big question is how much do you need.

The tire needs about 1 degree to start with. With most suspensions discussed here, there will be a gain of 1½ degrees to 2 degrees per inch of bump travel. If your suspension has 3 inches of bump travel, that would add up to 4½ degrees to 6 degrees. Add in the 1 degree negative initial setting and you have 5½ to 7 degrees negative at full travel.

This is best accomplished by blocking the chassis and removing the spring. Then the suspension can be moved through an arc with a jack. Set the camber at full bump travel. The car should be level. Then with the spring replaced and the car on its wheels, measure the camber. From now on that will be your static camber setting on the right front.

A problem with some stock car suspension mountings is they dont allow all the caster needed while providing enough camber. Split the settings, if necessary, by removing a degree of caster and a degree of camber. Just keep the caster stagger the same.

Camber on the left front will not be the same as on the right. You will need positive camber on the left front wheel. There is little camber change as the left front goes down, the reverse of bump travel. Therefore, an initial setting of ½ to 1 degree positive camber will work well.

Camber can be set using store-bought gauges. These allow you to adjust the wheel and use the angle finder to measure the camber. An angle finder with a magnetic attachment definitely makes reading easier.

Toe Setting

When setting up the car, it’s often not desirable to have the front wheels exactly parallel to each other. Some situations call for toe-out while others call for toe-in, thus the term “toe setting.”

The toe setting will vary with the type of track and the steering linkage. Long tracks and/or tarmac tracks may require toe-in at times. Most of our cars with stock-type steering linkages running the small tarmac track like Warton will need a bit of toe-out to work properly. This is not a case of “if some’s good then more’s better.” A toe-out of ¼ inch to 3/8 inch is about right for most. Too much adds drag. Too little will give the car an unstable feeling.

Toe is best measured some other way than hooking a steel tape in the tire tread on one side and going to the other side. The tire tread is notoriously less than straight on the tire carcass. When two people hold a tape across the tires, it is very difficult to keep the measured points the same distance from the ground. When the measuring points are not the same height on the tire, the distance between them changes. Instant error.

Toe boards are available that have saw slots in which to hook two steel tapes. These lay against the tire on each side of the car. They work OK when the tire has no bulges or raised letters.

Many of you Warton regulars may remember that aside from "Lordy's Ramblings" in the Warton programme I also used to write from time to time, Technical Info articles for the Petrol Heads. The above text is one of those articles...... not to be read as gospel but certainly an acurate piece of information which should provide those of you thinking about your own Stock Car project as a starting point .........