How do you adjust suspension and Gear ratios?

[coderiver]

Is this a level based thing? I can buy fully customized suspension and transmissions - but I cannot see anywhere that I can adjust them?
I am only level 10 - is that the problem?
Can you adjust the air pressure?

 

[speedthrill]

there's a thread inhere in Q&a section, wait i'm looking for it.

edit: here it is... https://www.gtplanet.net/forum/showthread.php?t=133754