In addition to the usual complement of gages, i have found my VDO fuel pressure gage very useful, i ended up expoxing a 22 gage hypodermic needle in its line to remove any gage fluctuation, so is very responsive, but does not flutter. I always watch that and my
oil pressure gage when i start my car, and i have found the fuel pressure gage very diagnostic when i had some hesitation at WOT, indicating a clogged fuel filter.
I have also put in a 20 PSI low
oil pressure warning sender in my
oil filter mount, with a red warning light on my dash, aimed right at my eyes. If i ever hole my sump, or lose pressure, i might not notice my oil pressure gage, so this will give me a heads up in time, hopefully.
I am going to put in a 220 degree water temp warning light this winter.
I like gages, many years ago, on my VW Type 3 Squareback, much modified, i had 8 VDO gages!! Enough that when they all ran, they bogged the motor!!!
I also have an MSD rev limit light mounted low, aimed up at my eyes. Sort of a "gage" i guess.