To the OP.
Tuners for gasoline engines are not as bad as you think. The trick is to have someone who knows how to tune for your specific needs write tuning programs you can load. The tune ups you get from the companies that build the tuners are very generic and do very little. They don't want to be sued when junior takes the car out and breaks something running it too hard.
I have a tuner for my car. I'm a certified mechanic and know what I'm doing so I used it to write my own tune ups for my car. I wont go into details, but with nothing but tuning, I was able to take a second and a half off the cars 1/4 mile times at the drag strip without any other mods at all.
