issue choosing turbo/naturally aspirated

[drvape33]

I have an issue, when I build a motor and go to choose either turbo or naturally aspirated it won't give me an option!! I can't click ANYTHING so I can't build it does this in sandbox and every other game mode. help please

[VicVictory]

Usually means on the previous screen (top end) you have forgotten to select VVT and/or VVL. If they're not available in the year of build, you still have to click "none" before anything on the aspiration tab will work.