Changing powertrain, gearbox, and ERS values do not change accurately

[PrizmR6S]

When using the all parts menu in parts, I'm trying to manually change the powertrain, gearbox, and ERS values to match that of the Honda engine (from the Mercedes engine) but doing so gives various inaccurate values to those I set

Screenshots

Additional context
If possible I just want to go back to before the season start to repick my engine supplier but all of the time jump options seem to be broken.
Modded File: https://drive.google.com/file/d/1b6UeGMqhxPM295R-9F3jeYeO070n13X3/view?usp=sharing
Original File: https://drive.google.com/file/d/1PwsXemBkiQgLI_6-uuALKqlFKh3NAl_9/view?usp=sharing

[gcorly]

what do the number in grey means ?
for exemple I have -4000 under fuel efficiency and I cannot start a race with enough fuel, I don't know how to change this.
(seems to me it's an issue with modifying engine...)
I tried to reset the initial value (50) but the minus still decrease and I had less fuel available