Car Controls without physics.

I need to Controls to my car with out rigid body. simply using trasform.traslate and rotate.
here is what i did.

accelarationInput = Input.GetAxis (“Vertical”);

SteerAngle = Input.GetAxis (“Horizontal”);

transform.Translate (0, 0, Speed * Time.deltaTime);

transform.RotateAroundLocal (Vector3.up, SteerAngle Speed 0.03f * Time.deltaTime);

but it is not giving realistic motion it is simple traslating and the rotation also bad.

public float accelarationInput;
public float SteerAngle;
public float gravity;
public float Speed;
public GameObject Pivot;

void Update () {
	UpdateAccelaration ();
	UpdateSteerAngle ();
}

void UpdateAccelaration()
{
	if (Application.platform == RuntimePlatform.WindowsEditor) {
		accelarationInput = Input.GetAxis ("Vertical");
	} 
	if (accelarationInput > 0) {
		Speed += Time.deltaTime * 40;
		if (Speed > 100) {
			Speed = 100;
		}
	} else if (accelarationInput == 0) {
		if (Speed > 0) {
			Speed -= Time.deltaTime * 25;
			if (Speed < 0)
				Speed = 0;
		}if (Speed < 0) {
			Speed += Time.deltaTime * 25;
			if (Speed > 0)
				Speed = 0;
		}

	} else {
		Speed -= Time.deltaTime * 25;
		if (Speed < -60)
			Speed = -60;
	}
	transform.Translate (0, 0,  Speed* Time.deltaTime);
}

void UpdateSteerAngle()
{
	
	if (Application.platform == RuntimePlatform.WindowsEditor) {
		SteerAngle = Input.GetAxis ("Horizontal");
	} else {
		SteerAngle = simpleJoystick.instance.H / simpleJoystick.instance.Radius;
	}

	transform.RotateAround(Pivot.transform.position,transform.up,SteerAngle * Speed/2 * Time.deltaTime);
}

it works great. if you don’t want to use physics in your car this is the best start up.