Or is that just someone else doing something and you pocketing the cash? Be honest. Is it your tune, or someone elses? if you REALLY burned chips, you would be able to take any car on a dyno, read the A/F and horsepower curve, and be able to make substantial changes in the right direction.
Most tuners that work on OBD1 cars take about 5 total chips MAXIMUM and about 2-4 hours to get it right.