Steven, there is a great deal of info. on these topics here. Hard to cover in a single post. Try some searches on each topic. Here's a little to get you started.
EGT: exhaust gas temperature, important especially with performance upgrades as 1300 F is considered a safe cutoff to avoid internal engine damage. If you don't know what the EGT is, you can't protect your investment as well.
pre/post pyro meter: EGT's measured either before the turbo (pre) and preferred if performance mods have been, or after the turbo (post).
boost meter: measure of intake plenum air pressure, limited to 21 psi on stock engines. Like EGT's, if engine modified to produce more boost (which by the way help lower EGT's) it's necessary to monitor to prevent over boost (debatable where this is but 45-50 psi seems to be the consensus)again to protect your investment.
fuel pressure: I'm sure you're aware of the lift pump problems reported here. Again to protect your investment, namely your injection pump, you need to monitor fuel psi.
trany temp: If you tow heavy or regularly, you'll want to know when to back off to protect your transmission investment.
Hope this helps
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Kurt Voss
********* 1999 2500 24VCTD AUTO 4x4 QC LB Laramie SLT, Luverne stainless steel nerf bars, 3 piece bug deflector, mopar mud flaps, Line-X bedliner, Blue Chip Fuel Management System (Premium), Psychotty Air, DD3's,TTPM, DD 4" exhaust, HX40, DTT VB/TC(91%) , Mag-Hytec transmission pan... YEEEEEHAAAA!!
[This message has been edited by work2muchplay2little (edited 05-11-2001). ]
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