It might help to know about types of under/oversteer as they occur due to different reasons. If you can understand them it will help you tune your car and avoid problems.
Understeer
- Going to fast into a corner can cause your front wheels to lose traction when you turn the steering. Just slow down more basically.
- Locking your front brakes will stop the steering axis from rotating and again you will lose traction. Brake earlier, ease of the brakes as you turn, turn down the front brake setting and try cadence braking and trail braking (you can find stuff on these if you search).
- Understeer during acceleration. In a FF car when accelerating out of a corner your front wheels have to do both the turning and apply the power. If to much power goes through the wheels they will lose traction. This also occurs in 4WD cars.
- In a FR, MR or RR car power understeer can occur due to weight transfering to the back wheels so the front wheels have less traction. Try stiffening the springs to lessen the effect of this. It can also help to adjust the LSD (see next point).
- To stiff limited slip diff will make your car harder to turn. If you think about how a tank turns one track goes one way and the other track another. If you LSD is to stiff its like both tracks (or wheels in this case) are not able to rotate seprately. However, if you make it to lose you will get oversteer.
- Understeer when riding curbs. The tyres lose tractions as they are lifted into the air by the ground. This usually only happens in race cars. On a side note I don't think GT4 recreates ground effect but its why most race cars run so low. Ground effect occurs when a car is running so low to the ground that a vacuum is created sucking the car to the ground meaning it can go faster through corners. See
http://www.absoluteastronomy.com/encyclopedia/A/Ay/Ayrton_Senna.htm
it gives you a bit of info about why Senna's car left the track causing his death.
Oversteer
- Going to fast into a corner can induce oversteer if your front wheels have more grip than your rears. Tends to happen more in fast changes of directions in GT4 more than other games. This is why people often say GT4 understeers compared to games like Forza. Either go slower or adjust the balance of the car by softening the rear suspension, increasing the rear camber, raising the rear downforce, etc. Or do the opposite to the front springs.
- Oversteer when riding curbs. The bumps cause a loss of traction and the back end lets go. Either the suspension is to stiff or you are bottoming out and need to raise the rear ride height or don't drive over the bumps.
- Power induced oversteer occurs when accelerating out of a corner in a rear wheel drive car due to to much power being put through the back wheels and the then lose traction causing the back end to spin out in the direction of the corner. Apply less power, use a higher gear or turn up the traction control. Note: this can be useful for turning the car faster and when controlled is whats called drifting as basically you end up moving sideways with the rear wheels drifting behind.
- Lift of oversteer doesn't occur much in GT4 but it does in the previous GT games. Basically the engine causes a braking effect when you lift off the gas. In a RWD car during cornering if you do this the rear wheels slowing causes a loss of traction compared to the front and the weight balance of the car to be thrown forward. This results in greater front wheel grip and less rear wheel grip meaning the back lets go and you go for a spin. This is why if you leave the asm on it will hold the throttle open during corners
- Locking your rear brakes will cause a loss of traction in the rear wheels so the rear of the car doesn't slow down as much as the front and when you go to turn it tries to keep going past you. If you saw the Monaco GP this is why Alonso got past by the Williams F1 cars. He had no rear grip left on his tyres so he had to brake alot more gently otherwise he would have spun at the chicane. Whereas the Williams cars could use there brakes to their full advantage to pass him under braking. Reduce the rear brake balance or brake more gently. Note this can be usefull in rallying as it allows you to get the back end round.
- Too low rear grip causes the same effect as above only it occurs during most turns (depeding on the cause) rather than just under braking. If its areo related then it will only occur at higher speeds.
These are the most common causes I can think of at the moment. There is lots of info about tuning and specific cars you will be able to find on these forums that will help.
Remember if you leave the TC and ASM on it will prevent you from experiencing most of these effects either by cutting power or preventing you from turning. Generally I use a bit of TC when using a DS2 as I find it difficult to press the buttons accurately. But I find ASM really slows everything down drastically.
Hope this helps
Meow! (='.'=)
