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integrale1
Junior Member
Madagascar
410 Posts |
 Posted - 11 May 2007 : 19:57:01
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Borrowed from another site
Toe
Front Toe-in Stabilizes the car in the straights, and coming out of turns.
It smoothes out the steering response, making the car very easy to drive.
Front Toe-out Increases turn-in steering a lot.
But can make the car wandery on the straights;
Never use more than 2 degrees of front toe-out!
Rear Toe-in Stabilizes the car greatly. It makes the rear end 'stick', but more toe-in makes the difference between sticking and breaking loose bigger.
Less rear toe-in makes the car turn faster and better
Rear Toe-out is never used. It makes the rear of the car very, very unstable.
Ride Height
Higher
The car feels better in bumps, and jumps better.
It can feel tippy, or even flip over in high-grip conditions.
Lower
The car feels more direct, and it can potentially corner a bit faster.
It's also harder to flip the car over.
Lowering one end of the car, or putting the other end higher up, gives a little more grip at the lowest end, but try to avoid big differences in ride height between the front and the rear.
Camber
Camber is best set so the tires' contact patch is as big as possible at all times.
Camber describes the angle between the tire's centerline and the vertical plane. If the wheels of the car lean inwards, the camber angle is said to be negative, if they lean outward, the angle is said to be positive. It is usually measured at ride height, and angles of -0.5 to -3 are the most common.
Negative camber is used to give more traction to the front or rear of the car around corners. Negative camber acts against the tyre preventing it from folding under around tight bends
If you would like to see the effects of how camber works, you can do this little test. Put fuel as if you were going to drive it. Look straight on at the front of the car. Turn the wheels left. Now push down the RIGHT side of the car, as if it was leaning into a corner. Take notice of how the front right tire is now flat with the ground. If it isn't, keep adjusting the tie-rods untill it is. This provides maximum contact area with the ground, which makes more traction. You will of course, need to slightly adjust the camber after that, depending how much bite the track has and how much your car is leaning into the corners.
First of all, positive camber is never used, only negative. Negative camber is necessary because when a car turn into a corner, it experiences chassis roll, which increases the tires' camber angle. Also, because most rubber tires are quite flexible, they get a little deformed in the direction of the center of the corner. If the car doesn't have any negative camber, only the tires' outer edge and sidewall would touch the ground, which isn't beneficial for traction. A tire's coefficient of traction (grip) increases as it's contact surface increases, so the ideal situation would be that the tire would stay perpendicular to the ground at all times, and that it wouldn't deform under heavy side load. Unfortunately, this isn't the case; most of the time you have to find the best compromise. The problem is that if you want maximum forward traction, you have to set the camber to 0°, and if you want maximum cornering action you have to set it to a few degrees negative, depending on the softness of the suspension and tire carcass. So you can't have both, but you can try to make the best possible compromise. The easiest way is to set camber so the tires wear evenly across their surface, that way you can be sure every part of the surface is used to the maximum of it's potential. Keep in mind that a car with very soft suspension settings and very little camber change will need more negative camber than a car with a very stiff suspension and In very bumpy offroad conditions however, it can be beneficial to use more camber than would be needed for uniform wear across the surface. The excess camber stabilizes the car in large bumps and reduces the risk of catching a rut and flipping over.
Caster
More caster increases steering drastically.
Steering feels much more direct, the car turns tighter and faster. caster aids stability, and handling in bumpy sections.
Less caster aids stability, and handling in bumpy sections.
Anti-Roll bar
Anti-roll bars are best used on smooth, and high-traction tracks only.
If you must use one on a bumpy track, try to use a very thin one.
Adding an anti-roll bar, or stiffening it, reduces traction at that end of the car. So it feels like the opposite end has more grip.
If the track is smooth enough, it also makes the grip level feel more consistent.
Anti-roll bars reduce body roll in turns, so they make the car feel more direct, and make it change direction quicker.
Stiffer Front
An anti-roll bar at the front of the car reduces low-speed steering. The turning radius will be larger, but very consistent.
It reduces 'hooking' by preventing front end roll.
The car will have more rear traction in turns.
Stiffer Rear
Adding an anti-roll bar to the rear of the car gives more steering. the car steers tighter, also at low speeds.
On a very smooth track, it can make powersliding easier. It can also make powering out of turns and lining up for jumps a little easier.
Bump Steer
Bump steer in generally undesirable. If the angle of the wheels does change as the suspension is compressed, the wheels should move outward. (steering less)
More bump steer can make a car have less steering, and be a little bit more stable in bumps.
Shocks
Damping/oil, Damping should always be adapted to the spring ratio; the suspension should never feel too 'springy' or too slow
Heavier
Thicker oil (heavier damping) makes the car more stable, and makes it handle more smoothly.
It also makes the car jump and land better.
If damping is too heavy, traction could be lost in bumpy sections.
Softer
Soft damping (and springing) is better for shallow, ripply bumps.
It also makes the car react quicker.
Heavier Front
The turn radius is wider, but smoother. The car doesn't 'hook' suddenly.
The car is easier to drive, and high-speed steering feels very nice.
Softer Front
The steering reacts quicker.
More and better low-speed steering.
Heavier
Rear Steering feels quick and responsive, while the rear stays relatively stable.
Softer Rear
Feels very easy to drive, the car can be 'thrown' into turns.
More rear traction while accellerating.
If one end of the car has slightly heavier damping than the other, then that end will feel as if it has the most consistent traction and the most stable when turning in and exiting corners.
Shock Pistons
The assumption is made that if pistons are changed, the viscosity of the oil is also adapted, to give the same static feel. (Same low-speed damping)
Smaller Holes
Smaller holes mean more 'pack'. Pack means the damping gets very stiff, or almost locks up, over sharp bumps, ruts, or landing off jumps.
Small holes are good for smooth tracks, with big jumps or crummy jumps with harsh landings.
Bigger Holes
Bigger holes mean less pack. The point at which the damping gets stiff (where the shock 'packs up') occurs a lot later, at higher shock shaft speeds.
Big holes are very good for bumpy tracks. The car is more stable and has more traction in the bumpy sections. It won't be thrown up over sharp bumps, the suspension will soak them up a lot better.
Smaller holes in front
The car jumps very nicely, a little more nose-up.
It feels easy to drive.
Bigger holes in front
Can give a subtle feel of more steering and more consistent front end grip if the track isn't perfectly smooth.
Always use the same, or about the same shock pistons front and rear. Big differences in pistons make the car feel inconsistent, and not very smooth.
Springs
Stiffer Stiffer springs make the car feel more responsive, more direct.
They also help the car jump a little better and higher.
Stiff springs are suited for high-traction tracks, which aren't too bumpy.
Softer
Softer springs are better for (mildly) bumpy tracks.
They can also make the car feel as if it has a little more traction in low-grip conditions.
Stiffer Front
The car has less front traction, and less steering. It's harder to get the car to turn, the turn radius is bigger and the car has a lot less steering exiting corners.
The car will jump better, and maybe a little further.
On very high-grip tracks, it's usually beneficial to stiffen the front, even more than the rear. It just makes the car easier to drive, and faster.
Softer Front
The car has more steering, especially in the middle part and the exit of the corner.
Front springs that are too soft can make the car hook and spin, and they can also make it react sluggishly.
Stiffer Rear
The car has more steering, in the middle and exit of the turn. This is especially apparent in long, high-speed corners.
But rear traction is reduced.
Softer Rear
The car has generally more rear traction, in turns as well as through bumps and while accellerating.
Internal Travel Limiters / Droop / Downtravel
More (less droop/downtravel)
The car changes direction faster, and corners flatter. It feels generally more responsive.
Adding a lot of travel limiters is only advisable on smooth tracks.
Less (more droop/downtravel)
Less internal shock spacers give better handling on bumpy tracks, and more and more consistent traction on difficult tracks.
The car also land better after jumps.
The end with the least downtravel will feel the most stable, and the most direct. But try to keep a balance (front and rear end droop about the same), especially on low-grip tracks.
Adding more internal travel limiters is a very effective way of reducing traction rolls, if not the most effective way.
Upper Shock Mounting Location
More Inclined
Has a more progressive, smoother feel. More lateral grip.
Less Inclined
(More Vertical) More direct feel;
Less lateral grip. (side-bite)
Generally a bit better for jumps and harsh landings.
Front more inclined than rear
Steering feels very smooth.
A little more mid-corner steering.
Mounting the rear shocks very upright can result in the rear end sliding in the middle of the turn, especially in high-speed turns.
Rear more inclined than front
Feels agressive turning in.
The car has a lot of side traction in the rear, and the turn radius isn't very tight.
Lower Shock Mounting Location
Bear in mind that changing the lower shock mounting location changes the lever arm of the shocks on the wheels.
So mounting the shocks more inward makes the suspension softer at the wheel, and mounting the shocks more towards the outside makes the suspension stiffer.
Front more inward
More low-speed steering.
Usually makes the car very hard to drive.
Front more outward
Makes the car very stable, but it has a lot less low-speed steering.
Rear more inward
Makes the car soak up bumps a little better, and can make the car corner a bit faster.
Can be good for bumpy, low-grip tracks, but general stability is greatly reduced.
Rear more outward
Feels very stable.The way to go for high-grip tracks.
Roll Center / Camber links
Long Link
A long link gives a lot of body roll in turns.
It feels as is the body is willing to keep on rolling, until in the end, the springs prevent it from rolling any further.
The car has more grip in corners, especially the middle part.
Short Link
A short link makes that the body doesn't roll as far, its tendency to roll drops off as it rolls.
This can stabilize a car in bumps and curved sections.
It feels as is the car generates a little less grip.
Parallel Link (Parallel to lower arm)
A parallel link gives a little more roll than an angled one.
It feels very smooth, and consistent as the body rolls in turns.
Angled Link (Distance between arm and link is smaller on the inside)
An angled link makes it feel as if the car has a tendency to center itself (level, no roll), other than through the springs or anti-roll bar.
It gives a little more initial grip, steering into corners. It makes it very easy to 'throw' the car.
The body rolls a little less than with parallel links.
On bumpy tracks, it could be possible to use softer settings for damping and spring rate than with parallel links, without destabilising the car.
Beware that you should always keep an eye on the balance of your car; large differences in roll center front vs. rear will make the car feel less consistent and less confidence-inspiring.
Longer Front Link
The front rolls and dives more in turns.
Lots of steering in mid-corner.
Could make the car hook.
Shorter Front Link
The front feels very stable.
A little more turn-in, but less steering in mid-corner
Longer Rear Link
More rear traction in turns, and coming out of them.
Rear end slide is very progressive, not unpredictable at all.
Make sure that there's enough rear camber though, or you could lose rear traction in turns.
Shorter Rear Link
The rear feels very stable. It breaks out later and more suddenly, but if it does, the slide is more controllable.
It makes the front dive a little more, which results in more steering, especially when braking.
More Angled Front Link
Turn-in is very agressive.
The front feels as if it wants to roll less than the rear.
More Angled Rear link
The rear end is rock-solid while turning in. It feels very confident.
Anti-Squat
More anti-squat generally makes the rear of the car more sensitive to throttle input.
The car has more steering while braking, and also a little more powering out of corners.
On high-traction tracks, it may feel as if the car momentarily has more rear traction accellerating out of corners.
A car with more anti-squat can also jump a little higher and further, and it will soak up bumps a little better, off-power.
A lot of anti-squat (4° or more) can make the car spin out in turns, and make the rear end break loose when accellerating.
Less anti-squat gives more rear traction while accellerating on a slippery or dusty track.
It also gives more side-bite.
Less anti-squat will make the car accellerate better and faster through bumpy sections.
Very little anti-squat (0° or 1°) makes the rear end feel very stable. It also makes power sliding a lot easier.
Note that anti-squat only works when you're accellerating or braking, it does absolutely nothing when you're coasting through turns.
The harder you brake or accellerate, the bigger the effect of anti-squat is.
Wheelbase
Shorter
A short wheelbase makes the car feel very nimble, and good in tight turns.
This is a good idea for very small and tight tracks, without big jumps or bumps.
Longer
The car becomes a lot more stable, and better in wide, high-speed turns.
This is good on wide-open tracks.
Wings
Rear
Adding rear downforce by changing to a bigger wing, or mounting he wing higher or at more of an angle increases rear traction at speed.
This can be very useful on slick tracks with fast, sweeping corners.
Hope this helps for buggy's and truggy's |
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reg
Junior Member
Christmas Island
427 Posts |
Posted - 11 May 2007 : 20:12:20
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you must be really bored |
Edited by - reg on 11 May 2007 20:12:48 |
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integrale1
Junior Member
Madagascar
410 Posts |
Posted - 11 May 2007 : 20:20:10
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Took me ages to type all that out ...p.s. mark answer your phone.. |
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reg
Junior Member
Christmas Island
427 Posts |
Posted - 11 May 2007 : 20:21:47
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| the battery is flat,its charging up, |
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grasshopper
Senior Member
1652 Posts |
Posted - 11 May 2007 : 20:23:51
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Brilliant piece of writing - certainly helps me understand more about vehicle geometery and the 'tech speak' more avid drivers use.
The only thing I would add is to do with aerodynamics - and more importantly the last bit about wings - one of the good side effects of big wings at the rear is not just to increase rear traction but to lessen steering effect at higher speeds - avoiding the potential of over controlling. The downside is obviously drag - and less speed. |
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integrale1
Junior Member
Madagascar
410 Posts |
Posted - 11 May 2007 : 20:26:01
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I didn't write it i just stole it |
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reg
Junior Member
Christmas Island
427 Posts |
Posted - 11 May 2007 : 20:46:55
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| and heres me thinking you new all that |
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reg
Junior Member
Christmas Island
427 Posts |
Posted - 13 May 2007 : 20:28:35
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have you got your setup board yet pat ps happy birthday you old git |
Edited by - reg on 13 May 2007 20:34:30 |
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integrale1
Junior Member
Madagascar
410 Posts |
Posted - 13 May 2007 : 21:04:51
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Cheers mark,and no its not arrived yet...ive got one hell of a hangover though |
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