30 psi
The 2007 Volkswagen GTI has 16 valves.
The 2008 Volkswagen GTI has 16 valves.
The 2014 Volkswagen GTI has 16 valves.
The 2013 Volkswagen GTI has 16 valves.
The 2010 Volkswagen GTI has 16 valves.
The 2009 Volkswagen GTI has 16 valves.
The 2012 Volkswagen GTI has 16 valves.
The 2011 Volkswagen GTI has 16 valves.
Yes you can use 205 60 r 16 tires in place of 205 50 r 16. They are only slightly higher.
Yes, that is a reasonable change.
Of course you can.