You either pay someone to burn a chip, or burn one yourself with some pricy equipment, not much improvement that can be made tho from what some say... Eddie says the best bang for the buck is a 180* Stat, I agree..... Efans could help.
Yes, the 180* t-stat mod really works. It keeps the Duke's engine timing near fully advanced, all of the time, while the programmed-in spark retard is still functional. If your truck has a non-clutch fan, or a clutch fan that does not work, then the e-fan option is out there. But I much prefer the KISS principle (Keep It Simple Stupid) and try to use the parts that are already engineered into the truck.
If you do not currently have the 180* t-stat installed, then run these tests: How hot is it really running on a warm day?? Check the coolant temperature right at the neck where the t-stat lives. Use an IR heat gun probe. If it is near 200* F. with the stock 195* t-stat, then it is TOO hot for stable timing. Put your timing light on it, without shorting the ALDL. Aim it right at the timing marks. Does the timing jump around?? Does the idle speed (ASSuming everything else is OK) follow it?? The Duke should speed up as the timing advances and slow down as it retards. It won't be stable at all, and is the cause of many issues I see posted here.
Toss in a sticky dick head on your EGR valve, and you have a real mess on your hands. The sensors chase this idle speed variance all over the place, and make a bad situation even worse.
Once you install a 180* t-stat, one that has been checked for proper operation, run the timing light check again. The timing will still hop around a bit, but it will be much more stable..good luck..