App Script Array Push() in loop Optimization

Question

I'm looking to improve my array push inside loops but I noticed that every time my function is being called (in a loop manner) and executing this lines of code, it gets slower and slower. It is fast when I run this function once, but it gets longer when ran multiple times via loop.

My goal is to get the values from spreadsheet and assign them to an array with a specific arrangement so I can retrieve those data accordingly.

I need to have the spreadsheet call in the loop as I need to extract the address from the array parameter.

function testing(dataCollected){
 var i=0;
 var finalArray=[];
 
 while(i <=dataCollected.length){
  projCode = dataCollected[i][0];
  unitNo = sheet.getRange(dataCollected[i][1]).getValues();
  hours = sheet.getRange(dataCollected[i][2]).getValues(); 
 
  for (var j=0; j<=81; j++){
     finalArray.push([projCode,unitNo[j][0],hours[j][0]);
  }
  i++;
 }
}

Does using push() create an overhead in this situation as it gets larger as I append row in it? Can someone advise what is the best approach to do in this setup. Thanks.