There is no steering pump as the Z4 uses electrically-assisted steering.
On my 54 reg, its the middle of the steering wheel.
There is no power steering fluid..........all electronic.
The 2012 BMW Z4 has 16 valves.
The 2005 BMW Z4 has 24 valves.
The 2009 BMW Z4 has 24 valves.
The 2008 BMW Z4 has 24 valves.
The 2011 BMW Z4 has 24 valves.
The 2010 BMW Z4 has 24 valves.
The 2014 BMW Z4 has 16 valves.
The 2003 BMW Z4 has 24 valves.
The 2007 BMW Z4 has 24 valves.