[al lkosmal]

Frank,
Lot's of good info in this thread and I'll add my $.02..... regardless of mode, if you have a tune that has your 911 running pretty well, I think you are ahead of the game if you move forward to refine that tune to meet your specific engine configuration/characteristics. I supply good start-up tune files with the systems I provide and they work great, to get you up and running quickly, but then the real tuning begins. There is no substitute for gaining a basic understanding of the principles involved, data-logging.....reviewing the logs, understanding the results and the basics of how to modify the tuning to improve the results. This can be done on a dyno, but excellent results can be had (and better in some cases IMHO) by driving/data-logging/modifying...rinse and repeat until satisfied with the results.......It is definitely a process.

regards,
al