No you don't NEED one if you don't plan on running more than 14 PSI of boost. However if your goal is running up to 29 PSI and reading the boost you will have to have one. Since the MAFT pro has a lot of tuning based on default settings around 0 and 6 PSI You should have a MAP sensor hooked up. The factory 2 Bar map sensor on analog dash cars will work to get you running and is on the passenger fender. The MAFT Pro should have instructions for the wiring and be sure to set the correct settings in the MAFT Pro menu so it knows what sensor you are running.
All that said, my suggestion to anyone considering a MAFT Pro is to read the instructions until you can't think of any more questions to ask, and then come back here or to the MAFT Pro site when you realize there is more to it. The learning curve on it is fairly steep for most at first but if you make it to the other end of the tunnel it is worth the ride IMO.