okay so i bought a diablosport off some dude on craigslist for 80 and its not vin locked, so i wanted to ask the people who are more familiar with ls1s and the tuning a few things....first and most importantly is there anything i shouldnt do? and how can i get the best performance without getting a custom tune?...im pretty much stock just a slp lid, slp filter, and slp catback on my 02 ws6 "a4"

 

what revision is that predator on? power it up and when it gets to the main menu, the revision number is shown at the top of the screen...

 

You didn't try it before you bought it? Here's what the U7198 (what yours SHOULD be) works with-

1999-2002 Silverado, Sierra, Tahoe, Suburban, Denali, Yukon, Avalanche V8
1999-2002 Cadillac Escalade
1999-2002 Camaro/Firebird LS1
1999-2003 Corvette LS1/LS6

Plug it in, and check the tuner status on it. It's either locked, or it's the wrong one.

 

No i didnt try it because i didnt take my with me when i bought it i was in thr neigh orhood so i just stopped by the dudes place and picked it up, however its not locked, i just cant seem to find what part number this diablo is?

 

how do you know it's not locked???

when you power it up and it's at the main menu, there's a revision number shown at the top of the screen.. what is that revision number?? should be a 1.xx, 2.xx or 9rxx number...

also, go to options - show last tune written - and what does it say?