Originally posted by TourDeForce:
What, exactly, is tunning?



Tunning is basically makeing a few runs to get a base line. Then you take those numbers, along with other informationaly items such as the A/F (air/fuel ratio), and makeing adjustments to the car to improve those numbers.

Let's say you got yourself some cam gears installed. You would make a few runs to get your baseline information about HP, Torque and your A/F. You then install your gears and set them to a base setting. Make a run or two to get an idea of where you are. Make some adjusts and continue until you have reached an "optimium" setting that allows you to reach a goal with your HP, TQ & A/F.

You might hear a lot of chatter about needing to go "tune" or "not running it hard until they tune it" from guys that have 3L Hybrids and F/I'ed beast around here. Most of all of them are running a custom burned (or tuned) chip in their ECM. What they will do is get their baseline, then begin to tweak all sorts of settings for things like the MAF sensor and injector pulse's, timing, etc... etc... What they will do is tweak things, by looking at exhaust gas temps and the A/F to find a "optimium" setting for all parameters that will allow for the proper A/F ratio (which by the way, was quickly found to be the killer of many of the first F/I'ed & 3L's around here) coupled with happy mix of HP and TQ. These settings are then burned into the chip, allowing for a custom tune.

I hope I was able to answer that without going too over bored.

Phillip Jackson `98 Mystique LS 262K+ and counting... ATX rebuilt @ 151K "This storm has broken me, my only friend!" RIP Dime