Endless runner, road segments spawn speed

Hi, I'm trying to make endless runner, character is still but ground is moving. So the problem is that ground is moving to fast and spawn speed to slow, I can't make it proportional.

 function Update () {
     
     var translation: float = Time.deltaTime * speed;    
     transform.Translate(-translation, 0, 0);
     meters = spawnPoint.transform.position.x;
     var increased:float = ((-1)*meters)- ((-1)*previousMeters);
     if(myTimer > 0){
         myTimer -=Time.deltaTime;
         Debug.Log(myTimer);
     }
     if(myTimer <= 0){
         lastPositionRegister(meters);
         positionOfNextSegment2 = positionOfNextSegment2-increased;
         myTimer = speed;
         removeFirstFromList();
         addLast();
         destroyFirst();
         spawnOnlyNew();
     }

Any thoughts for making it proportional? myTimer - counts spawning delay time, o translation is for moving ground.