How long can you run without a tune after header install?

[Street Fighter]

Want to get long tubes,but I live a good ways from the nearest tuner, about 200 miles. just how long can I go without a tune even if the car runs rich?

[Mr. Luos]

How ever long the car runs.
Tune isn't a need after LT's. Just something that would maximize the mod.

[Anthracis]

I got all my mods done first before I got it tuned. The car ran fine but not nearly as well as it could.

[fatelvis7]

GM pcms have a beautifull thing called fuel trim: This is a correction factor between what the MAF sensor says is necessary and the actual oxygen level at the O2 sensors, the headers will cause a shift in the efficiency of the motor but with the exception of first start up , the pcm will over timecorrect any(within reason) deviation. I have gone as far as to leave a large vacuum line off and watched the fuel trims correct up to %50 and had a vehicle still run reasonably well.
It wont run perfect mindyou but you wont damage anything.