As an aside, tire gauges can be off by quite a bit. My previous cheap tire gauge read 4-5 psi higher than the Accutire Racing Gauge I recently acquired. Its appeal was that it locks onto the valve very well w/o leaking. No more press on, wait for the hiss, hope the hiss stops, and then hope it got enough air that it's not reading low. Also, it has a bleed valve so you can pump it up slightly hire than your target pressure and then bleed it down to the pressure you want.



http://www.autogeek.net/racing-tire-gauge.html