How accurate are the temp readings between a normal gauge/pryo and what the juice (or hot juice) moniter shows? My buddy's claiming it's hard to get to 1300 with the Hot Juice on 5, pryo pre-turbo (between 3&4), it's a stock 600 except intake & straight pipe. I'm thinking it should be hotter then that. I'm a right? I just don't want anything to happen to his truck if the readings are inaccurate. Should he still put in an aftermarket temp guage? Thoughts?