You can only put turbos in the historic right? You can undo the changes, install and uninstall whenever you want. But if there are upgradeable engine phases to install, I wouln't go that far, since those are irreversible changes.
Or you could gift them to your 2nd account as they are (reload your data with them on) then gift them back now you have 2 one as stock one for complete upgrades.
Well, I don't know if they become useless because I only have the Jag and haven't even used it yet, but I have to tell you that, personally, I prefer to leave my race cars stock, maybe upgrade the tires to mediums or even softs, but no extra power. That's only my opinion, you are obviously free to do whatever you want
I maxed out the Jag in order to beat the Historic Meeting, it became a beast, but the suspension quite didn't couple the increase in horsepower. Needs a bit of softenin. Too stiff and jumpy at high speeds.
