I wonder if they're design is like GM's. ( they have been using both for quite a while now ) GM runs the MAF system for primary fuel / timing contol. the MAP sensor is primarily for EGR monitor self diagnostics. PCM looks for MAP change when it opens the EGR valve, if it doesn't see a pressure change when the valve is opened, it sets a code for insufficient EGR flow. MAP sensor is also a back-up for MAF sensor in the event of failure. Late GM PCMs are very smart and also use a 'rationality strategy' of monitoring TPS, MAF, MAP, to make sure that all the inputs are plausable -what is expected for the particular driving condition. If something is askew, the PCM can figure it out easier. The Viper motor does not use an EGR valve, so I wonder what their deal is.