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Accurate Tire pressure Gauge

I went to check my tire pressure and had a big surprise waiting for me. I used a digital one I picked up from the auto parts store thinking it should be fairly accurate, check the first tire, it said 50lbs, wow! tried and old pen type and read 39lbs, then a dial type and it read 28lbs. Now I'm not sure what to believe. The one thing I didn't try was the one on tire pump combo kit in the trunk, I won't touch that unless I have too. I took my gauges to a Mr. tire and they checked them and the dial type was the most accurate, only off by -3lbs. That's close but I was wondering if there was anything better with out costing some ridiculous price.
I want to get one of these Autometer ones because I have experienced the same thing. No accuracy.
Thanks for the link, I would think TP is pretty important in NASCAR. Moroso seems to have some nice ones too, but 40 -50 bucks for a pressure gauge seems steep.
racered302 said:
cloud9 said:

They bring up an interesting point with pressure release on the liquid filled ones, never considered that. I guess I need to educate myself on this. Thanks.
It's great at the track when you're trying to set starting pressures. You just hold the gauge on the stem and push the release button to air down to your desired pressure.
Things to think about when purchasing a quality tire gauge

PSI Range ~ The most important decision is to get a gauge that works within the pressure range of the tires that you will be using the gauge on. For example, if you run 30 psi in your tires then you should get a 60 psi gauge. If you run 15 psi then you should get a 30 psi gauge. All tire gauges work best in the middle of their range.

PSI Increments ~ PSI increments are another thing to consider when choosing the correct gauge. The finer the increments, the more accurate reading you will get.

Digital ~ Digital gauges are great, however the cheaper the sensor the less accurate the gauge is. With these gauges you get what you pay for.

Analog ~ Analog gauges are a great unit of measurement for the money. Normally, the bigger the face size the better the gauge is.

Face Size ~ The larger the tire gauge the more accurate it is, in most cases.

Hose Length ~ Longacre has 2 different hose lengths available, 14" and 17" for those hard to reach areas.

Chucks ~ Longacre has a swivel tire chuck and a standard non-swivel tire chuck. The swivel chuck is a very nice way to go. If the hose gets twisted up you can correct it with a swivel chuck

Holds Pressure ~ Do you need a gauge that when you check the pressure you can still read it when you pull it off the tire?

Bleeds air ~ All Longacre tire gauges will allow you to bleed off air when checking the tire pressure.

Protective Bumper ~ All Longacre tire gauges have a protective bumper.

GID Face or Backlight ~ Do you race at night or in a poorly lit pit area? If so maybe you need a GID (glow-in-the-dark) analog gauge or even maybe a backlit digital gauge.

Liquid Filled ~ Here is the scoop on liquid filled tire gauges. Liquid is used to soften the blow of air pressure when it enters the gauge. Just think, if you have 30 pounds of pressure then you have 30 pounds of pressure blasting the gears inside the gauge. That abrupt movement inside the gauge is what wears them out. However All Longacre tire gauges have a dampening system built into the gauge head that softens the blow of air pressure, therefore helping to protect the gears.

Case Included ~ The most important way to keep your gauge accurate is to keep it in a foam lined case. When your gauge is getting bounced around in your tool box while hauling it to the track or getting dropped, it will lose its accuracy. Keep your gauge in a case at all times when possible.

This is the gauge I have.............$45,000 Boss 302: check / $1,200 Nitto NT01s: check / $150.00 for a gauge: Not out of line............
Longacre makes great stuff. I have this:
Well, you guys have me sold on the Longacre. I appreciate the input. Now I have to decide on which one. Earlier in the post I said 40-50 was steep, but you do get what you pay for. Thanks again.


Too Hot for the Boss!
Longacre here. Another thing to remember is that you should always use YOUR tire gauge. Even though I think mine is super accurate (it is damnit!), I have used it on other cars with direct comparison to fellow racer's gauges... and they have been different by a couple of PSI. By always using YOUR gauge, it helps solidify that your settings are correct.
After you have a run history running the same gauge you are really only measuring difference. I have bought several pricey gauges and checked them against lab certified gauges and none not one was acurate. Only certified gauges with test certs can be trusted. That being said the design used on almost all analog gauges is very very consistant. As a result if you gauge your tires cold in the morning and later they gained four pounds in the sun, you can be confident they gained four pounds. If you have a nice gauge find a guy at the track who has the mega dollar whiss bang gauge and check a tire with his and yours note the difference. You have just done a red neck cert and saved a bundle. Put a piece of tape in the middle with + or - the difference and you now have a good gauge. If you have a nice gauge and the chuck, bledder, and hose are good but you do not trust the gauge replace just the gauge. McMaster Carr mail order has a number of certified gauge heads. Thats what I did. Replaced a Longeacre head that was not cheap and would give a different reading every time.
fiddlefadel said:
2012YellowBoss said:
My Sears Craftsman one works perfectly, pick it up on sale for 20 or 30 bucks.

Scott which model?


Dave it is packed in the truck for this weekend, I will look for you when I can. In the mean time it is digital with a light and button to release pressure. As far as I know it is accurate, if I leave a tire inside and check it under the same temp day after day it reads the same. I never checked a pressure twice quickly and saw two different reading.

I think the normal price is around $40 and it is not in the tool section but in the auto repair part of the store.


I ordered this one today.
Called and talked to the nice lady, and she said all of their gauges have the dampener to prevent the gears from getting blasted with the initial air shot. So the only advantage to the liquid filled is that the needle moves smoother.
Her basic decision making questions were:
Do I want it to hold the reading after I remove the chuck? Yes
Do I drive at night (need glow in dark or lighted)? No
Want swivel angled chuck to get at short stems? Yes
How are your eyes--bigger gauge easier to read. Medium size good

Those 4 questions rapidly got me to the model I ordered. Sure, I could buy a $300 electronic that stores the 4 pressures as I move around the car, but she said thats way more than I need.
Drivers that have the Pro Precision with the 4" dial and .5 lb incriments definatly have a very high quality gauge.


#LS-378 - So many Porsche's, so little time....
Wayne - I have the 4" one but's only becuase of my eyes - my contacts are good only for anything about 4 feet out or farther ! ;D I like the Longacre ones. I'm not sure how accurate they are but they seem precise (give the the same reading for the same pressure every time).


Is that why you bought the black LS--so you can always find it? ;D
Don't remember if you've ever posted that you're married, but what you're saying is inside 4', she always looks great?


#LS-378 - So many Porsche's, so little time....
drano38 said:
Is that why you bought the black LS--so you can always find it? ;D
Don't remember if you've ever posted that you're married, but what you're saying is inside 4', she always looks great?


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