Yes, the best way is to install an app called IntelliBoost. This will allow you to program the most effective ERS profile, which is how real LMP cars are configured. Alternatively, you can leave the MGU on Charging and use the KERS button momentarily at the best points on the track the best performance, but this is totally unrealistic as LMPs cannot change their profile on the fly neither did they have KERS push to pass buttons. If you want it to be most realistic, the grab the URD PX package too (payware), as these closely replicate the KERS capacity limits and deployment limits per lap.