No, it has a timing chain.
The 2007 Lexus IS-350's engine produces 306 hp @ 6400 rpm.
The 2007 Lexus IS-250's engine produces 204 hp @ 6400 rpm.
The 2007 Lexus GS-450H's engine produces 340 hp @ 6400 rpm.
The 2007 Lexus ES-350's engine produces 272 hp @ 6200 rpm.
The 2007 Lexus RX-350's engine produces 270 hp @ 6200 rpm.
The 2007 Lexus LS-460's engine produces 380 hp @ 6400 rpm.
http://www.clublexus.com/forums/showthread.php?t=338155
The 2007 Lexus IS-250 has a V6 engine.
The 2007 Lexus IS-350 has a V6 engine.
The 2007 Lexus LS-460 has a V8 engine.
The 2007 Lexus ES-350 has a V6 engine.