Thread: PCM tune

I feel stupid asking this but could someone explain to me what a PCM tune is? I have read about custom tunning and "canned Tunes", is a canned tune a predone thing or somthin that has to be installed at a shop? Any info would be awsome Thanks guys!

take the time and read this http://www.grandprixforums.net/f81/s...car-17482.html

Basically there are 2 programs out there to tune OUR gm 3800 cars right now. One of those programs called powrtuner is no longer sold, the other one is hptuners. Basically, the vendor uses one of these programs to change values/files in the pcm that will hopefully make the car run better. For instance, sometimes when installing a cold air intake or headers/flow mods, the car will run leaner. So they change a couple of things to force the car to add more fuel at the right times. They might also change the line pressures or shifts to firm up the shifts in the transmission or shift at higher rpms. There are a lot of things that you can change. Since every car is different and its hard to get something that will work well on all cars, they call it a canned tune from the vendor. A custom tune would be created by someone who physically scans the specific car and changes the tune according to the results of the scan. It is a more accurate way of tuning the car to be able to perform well.