You need a CTO in order to manufacture very high level upgrades.
The level to which you can upgrade a part depends on your CTO. Look at his Basic Stats to see up to what level he can upgrade each part.
Don’t forget to choose your upgrades related to the cup you will join. Because some cups have restrictions, and some cups have level limits at some upgrades.
By purchasing a contract for an upgraded part, you won’t automatically improve your stats. Once production time has finished you can then enable the upgrades in the races, using the Configuration tab on your racing page.
Upgrades use the ‘slots’ on your chassis, you also get extra slots when you get a CTO, how many depends on your CTO.
The cost of upgrades may go up with depending on the amount of drivers you have.
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