Its a wider duration cam by 14 deg's and as a result the full lift occurs 2 deg's out when used on the standard pulley. Its not been advanced as such.

By adjusting the timing normally a small improvement or loss will be noticed in either midrange or top end power.

If it was twin cam you have a lot more options coz you can adjust the valve overlap.

[IMG]http://i13.photobucket.com/albums/a2...1/01070007.jpg[/IMG]i can still get them made, usually in batches of six. They were £72 inc having your original pulley machined. I have a couple of peeps interested in them, so if you want one put your name down.
Cheers

picture added