i use infinity loop (which is 100% needed for this purpose) and i am allowed to use it
That’s interesting XD Infinite loop will stop your game instantly and there’s no possibility to allow you to do so
You can think of an infinite loop in some cases but in fact - it’s not because like said - you’ll be thrown out of PIE
But at least that was a funny sentence 
And about your system itself - you could easily use Custom Events with Timers which you can control easily and so make it grow or get smaller and once it hits the desired size or whatever - you stop the timer, do stuff