Sorry I missed this message over a month ago!!

On my 2007 MC SS I'm currently running Enkei RPF1s. 18 x 9.5" +45 offset with 70.3 bore. Used hub spacers 70.3 to 73.1. Tires are now Mickey Thompson Street Comp 255/45r18.

I was running Velox18 x 8 +40" offset wheels with Firehawk AS 2 245/45r18. These seemed a bit harsher compared to the 255/45s.

The stock 2001 LS setup (225/60r16) to the 245/45r18 option, will lose an inch of rubber. That's considerable, but it's almost the identical overall diameter (~26.65). You get more tire with the 255/45s, and even more with 235/50r18. Personally, I like the 255/45s. I think for performance getting a wide enough wheel to match the tire width is important, and it probably makes the ride smoother as well.

The 16" stock wheels are 6.5" wide (165.1mm) vs. a 225mm (8.86") wide tire. That's a narrow wheel compared to tire width for me. The Velox wheels @ 8" wide (203.2mm) vs. a 245mm wide tire (9.65") wide tire is closer.