[klrv6]

OK, I've just picked up a Jet DST programmer for my '99 suburban 2wd and 03 regal. What are the best know parameters to modify or change in order to see mileage improvements? I have already done some work on the suburban, dropped idle rpm by for most temps and bumped up timing four degrees from 2000rpm and 20kpa down. I plan on running some logs via auto-tap and see where the engine load and timing are during 70-75mph cruise settings. The software can touch pretty much every table within the ECM.

I have removed the roof rack and installed an efan with positive results. Just the roof rack and and new michellin tires yield 21-22 mpg (scangauge) on the highway.

Where should I start tuning for max mpg on this thing?