I have one and its never worked right so I took it out. Max boost it would read was 22 and my mechanical gauge pegs 30.
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04.5 2500 4wd, 6 speed, 3.73 gears Mods: 4" Superlift, 315/70/17 BFG A/T's, Silencer MIA, Thuren track bar, diPricol boost, egt, and fp gauges, Crazy Larry