Can anyone point me toward a good source of info on understanding all of our engine parimeters? Or turbo engines in general? I really can't find anything about them on www.stealth316.com. I understand pretty much what everything is for except what the hell the fuel trims are. :dunce: Some of the other things I understand, such as the knock sensor, and timing advance, but I'm unsure of what to make of the numbers, like where they should be. I'm confidant on using and understanding the S-AFC, but the only real data I'm sure of is my O2 voltage. (blue wire mod + a/f guage) Also EGT ranges. Whats too high, too low etc. I've got pretty much every tool to start basic tuning (MBC, A/F guage, S-AFC w/blue wire mod, pocketlogger on the way, EGT guage on the way) but I need to learn more about the sensors, thier values, and optimal ranges. Any links or info would be great, I'm sure this has had to have come up before, I just can't seem to find anything.