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Steering question

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Bob--

"All over the place" is relative. The one I carry when I am racing--and used to check the tires of the 100 yesterday--is a Longacre liquid-filled 0 to 30 psi model. It may vary a bit but probably not by more than 1/2 # psi. The pencil-type I used when I came in from the driving last weekend is obviously way out of whack and shame on me for not double-checking its reading at the time, which would have saved me and everyone else on the forum considerable and unnecessary reading/writing.
 
I have at least 4 gauges--two digital and two round-dial (Bourdon tube?) type--and no two agree with each other. The new digital claims '1% +/- 0.5psi' accuracy--it reads out to the nearest half psi--so it's the one I choose to believe for now. My best friend found one that agrees with the TPMS on his newly-acquired Porsche Cayman S so he believes it. Unless yours is calibrated to a known, certified source it's still a guess.

Best I've found are 'Certified ANSI Grade B40.1 (± 2%),' so my 'good' digital is suspect as it doesn't indicate which standard it complies with:

https://www.dascosales.com/pressure-gauge-accuracy.php

When I get a new set of tires I measure the wear to get a pressure that yields the most even wear across the tire width. I'm presuming even wear = biggest contact patch.

Researched the Longacre; looks like a good one, but 'Liquid filled gauges have many advantages. But they can change readings by as much as 2-3 psi if the temperature changes...' Does yours have the vent to equilibrate to the atmosphere?
 
"Does yours have the vent to equilibrate to the atmosphere?"

Umm...I dunno.
 
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