Car controller

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

[RequireComponent(typeof(Rigidbody))]
public class CarController : MonoBehaviour
{
    public float torque = 5000;
    public float brakingTorque = 10000;
    public float maxSteer = 45;

    public List<WheelCollider> backWheels;
    public List<WheelCollider> frontWheels;
    public List<Transform> wheelMeshes;
    public List<Transform> springMeshes;

    public float downForce = 1;

    public float ForwardVelocity { private set; get; }

    List<WheelCollider> wheels;
    Rigidbody rb;

    float throttle = 0.0f;
    float braking = 0.0f;
    float steering = 0.0f;
    float minSteering = 0.1f;

    // Start is called before the first frame update
    void Start()
    {
        wheels = new List<WheelCollider>();

        foreach (WheelCollider wheel in backWheels)
            wheels.Add(wheel);

        foreach (WheelCollider wheel in frontWheels)
            wheels.Add(wheel);

        rb = GetComponent<Rigidbody>();
    }

    // Update is called once per frame
    void FixedUpdate()
    {
        throttle = Input.GetAxis("Vertical");
        braking = Input.GetAxis("Jump");
        steering = Mathf.Lerp(steering, Input.GetAxis("Horizontal") * Mathf.Max(minSteering, 1.0f / (0.04f * ForwardVelocity + 1.0f)), Time.deltaTime * 10);


        foreach (WheelCollider wheel in backWheels)
        {
            wheel.motorTorque = throttle * torque;
        }

        ForwardVelocity = rb.velocity.magnitude * 3.6f;

        for (int i = 0; i < 2; ++i)
        {
            WheelCollider wheel = frontWheels[i];
            wheel.steerAngle = steering * maxSteer;
            springMeshes[i + 2].localRotation = Quaternion.AngleAxis(steering * maxSteer, Vector3.up);
        }

        Ray downRay;
        RaycastHit hit;
        for (int i = 0; i < 4; ++i)
        {
            WheelCollider wheel = wheels[i];
            wheelMeshes[i].Rotate(wheel.rpm / 60.0f * Time.deltaTime * 360.0f, 0, 0);
            float distance = 0.2f;
            if (wheel.isGrounded)
            {
                downRay = new Ray(wheels[i].transform.position, -transform.up);
                if (Physics.Raycast(downRay, out hit, 1.0f, ~(1<<9)))
                {
                    Debug.Log(hit.collider.gameObject.name);
                    distance = hit.distance - 0.42f;
                }
            }
            distance = Mathf.Clamp(distance, 0.0f, 0.2f);
            springMeshes[i].localPosition = new Vector3(springMeshes[i].localPosition.x, -distance, springMeshes[i].localPosition.z);
        }

        foreach (WheelCollider wheel in wheels)
            wheel.brakeTorque = braking * brakingTorque;

        rb.AddForce(-transform.up * downForce * ForwardVelocity);
    }
}