I'm not sure what you mean by "delay". If you mean a lag, a period of time in which power delivery is postponed, I don't think the Acceleration setting affects this. Based on my experience with 2018 and 2019 Levos the Acceleration response determined how rapidly power delivery ramped up. It seemed like you could set it to come in quickly over ~100 msec up to slowly over ~1 sec (very rough estimates!). The 100% "Race" setting on earlier models proved a bit much for some situations where subtle control was required. Too fast of full power delivery could cause problems. - an example would be negotiating a tight uphill switchback. I also noticed that faster Acceleration settings tended to use more battery presumably due to increased power demand. Your trails and riding preferences/skills will determine what works best for you.