You might want to measure your IC efficiency. If you turn up the boost you will most likely increase intake temps. If your Ic isn't cooler your intake very well then you might want to remedy that before you start pumping more and hotter air in the cylinders. Another thing is be sure your A/F ratio is not closer to lean already and have a way to alter your A/F in case is starts getting leaner when you increase boost.
I would say the easiest and most inexpensive way would be a manual boost controller.