I am looking to spend not more than $500.00 to chip my 04 Audi a6 s line 2.7t, does anyone know which chip would be the most beneficial (in terms of performance) for high altitudes (living in Denver)? I heard the APR is a good choice, but I want to be 100 % sure before I purchase one.

 

I'm in Colorado Springs and have been having the same thought. I contacted a few performance tuning shops in Springs and Denver and they all replied telling me they leave the modules unaffected which is supposed to be the best way to go.

So in that perspective I am considering the GIAC tuning not for a huge increase in power (I have the NA V8 engine, so not much to gain) but more for a stable increase in higher RPM range. I'm also able to combine that with the unique GIAC transmission tuning which will probably get the most out of my car (crossing my fingers the tranny will hold up) - down to 0.2 seconds shifting speed.