Actually it's an 3.0 liter 2995 182.8 cu. In. 24valve four cams v6 v-type 4cycle gasoline engine.
The 1998 Lexus GS300 uses the 2JZ-GE Toyota engine, which has 6 cylinders (inline-6).
The 2004 Toyota Avalon has 24 valves.
The 2005 Toyota Avalon has 24 valves.
The 2014 Toyota Avalon has 24 valves.
The 2008 Toyota Avalon has 24 valves.
The 2010 Toyota Avalon has 24 valves.
The 2013 Toyota Avalon has 24 valves.
The 2002 Toyota Avalon has 24 valves.
The 2011 Toyota Avalon has 24 valves.
The 2003 Toyota Avalon has 24 valves.
The 2009 Toyota Avalon has 24 valves.
The 2006 Toyota Avalon has 24 valves.