Your recommendations - Digital Tire Pressure Gauges

[DaveW]

I searched for this online, but was not satisfied with the amount of detail available, so I'd like to get some opinions from users here.

I am going to get a digital tire pressure gauge soon, mainly for racing my F2000 (tire pressures between 15 and 30 psi). If possible, I'd like to also use it for higher pressures (daily driver cars, tow vehicle and trailer, etc. up to ~80 psi).

I want accuracy within 0.5 psi and repeatability within 0.2 psi at least up to 30 psi. Additionally, I want it to read in 0.1 psi increments plus be durable and able to withstand normal racetrack abuse w/o failing or changing calibration. I want the type with a reasonably long (17-18 in) flexible hose, preferably with a swivel hose joint. I don't need or want "temperature-compensation."

I'm willing to spend in the $100-150 range (or slightly more) if that is necessary to get a high-quality gauge.

What would you recommend?

[problemchild]

i have had different Longacre digital gauges and found them all good, and close enough to each other, that you could use them on the "wrong" car without it being a big issue. The reason I might pay more for one than another, would be to get one that saved the readings. It simplifies the recording process, but also keeps your values private when sharing the pitlane.

[David Ferguson]

I know this is quite a bit outside your provided budget, but we've been using this for the last few years. I don't think there is anything better:

https://shop.veracitydata.com/produc...e-gauge-50-psi

This was the Stack digital pressure gauge. This link is bad because they no longer offer that product.

[Hardingfv32]

1) I would say check out Consumer Reports tests/recommendations. I can send a copy if you PM me.

2) The heart of a digital gauge is the IC/chip that container the pressure sensor. This is where all the accuracy and repeatability is found. There are just a few of these IC's commercially available with varying operating ranges. NONE cost more than a few dollars. The best gauges (most expensive?) would not have more than $10 in electronic parts in them in built in low volumes. The racing gage manufactures are not having custom chips made for their very expensive gages.

3) Some of the features you want will only be found on racing gages. You have to determine the cost/benefit for those features.

Brian

[DaveW]

1) I would say check out Consumer Reports tests/recommendations. I can send a copy if you PM me.

2) The heart of a digital gauge is the IC/chip that container the pressure sensor. This is where all the accuracy and repeatability is found. There are just a few of these IC's commercially available with varying operating ranges. NONE cost more than a few dollars. The best gauges (most expensive?) would not have more than $10 in electronic parts in them in built in low volumes.

3) Some of the features you want will only be found on racing gages. You have to determine the cost/benefit for those features.

Brian

I did check CR. Most of the gauges they reviewed are low-end stuff in the <$25 range. The issues with those were mostly related to poor quality resulting in a lack of durability and just falling apart after a short amount of use. Others did not maintain calibration. Many did not have some features I want, as you said. That's why I'm asking what folks on here actually use and like.

I trust racers a lot more than CR reviews.

[Hardingfv32]

User opinion over scientific testing.......

You are equating low price with low accuracy, repeatability and durability. That is clearly not what the CR test indicate is the case.

I use a Accutire. Very light and compact. Dropped many times, durability seems fine. You would have to hammer on it to get it to fall apart.

Brian

[DaveW]

Brian,

That kind of response is exactly what I'm trying to elicit. I'm not eliminating lower priced units per se. It's just that the reviews I saw of lower priced units were mostly negative, or their output was not in small enough increments.

Thanks. I'll look that one up.

That one might be OK if I could get it in to the valve stem - some of my wheels have the stem sticking straight out near the rim flange and it might be awkward w/o a flexible hose.

[Mike B]

Brian didn't provide a model #, perhaps it's this one:
https://www.amazon.com/dp/B000BNS7Y2/ref=emc_b_5_i

I'm guessing you could swap out the chuck for a ball chuck or something else more ergonomic.

[DaveW]

That's one of the gauges I read reviews (on Amazon) on yesterday - lots of issues with things going wrong with it - didn't give me much in the way of confidence it would last.

Please keep the opinions coming - I'm listening.

[romoman]

I'd tell you to go Longacre or the Intercomp. The other that is used at a high level (that I've seen anyone use) is from Ashcroft. They would all fit your specs but I'm not sure about the budget.

[Bob Wheless]

I'd tell you to go Longacre or the Intercomp. The other that is used at a high level (that I've seen anyone use) is from Ashcroft. They would all fit your specs but I'm not sure about the budget.

longacre

[DanW]

I've been using this 0-60 PSIG one for about 4 years. Most of the digital gauge batteries don't like cold weather. 45F is about the lower limit.
I did a cal check on mine with the calibration standard at work. It was within 0.1 PSI at 20 PSI and 0.2 PSI at 40 PSIG. It has held its cal every year when I check it. YMMV

http://www.longacreracing.com/produc...Pressure-Gauge

I had an accutire gauge for several years but died when I dropped it recently.

[Darren Brown]

Been using this Longacre for 15 years. Seems pretty accurate everytime I have checked it at work against some calibrated gauges. Measures in .1lb increments. Also has a backlighting so works good in the dark.

The draw backs of my longacre is the battery is always dead if left connected (probably the memory recall). I unplug the battery when not at the track. The memory recall works spotty at best.

Not sure they still sell this model though.


Just looked up the gauges, a lot more money than I thought but they are still made
http://www.longacreracing.com/produc...auge-0-100-psi

[DaveW]

I'm leaning towards the Longacre # 52-53000 60-psi digital gauge. It has very good specs:

Air pressure release button - Dual bleed buttons for even faster setting at lower pressures
External gauge bumper
Auto Off feature to save battery
17" hose with angle chuck - also includes ball chuck
Includes silver carrying case
User replaceable AAA batteries (2) included
0-60 psi with 0.1 psi increments
Accuracy: 0.3% (i.e., 0.1 psi @ 30 psi, 0.2 psi @ 60 psi)

Available at Summit Racing for $132.99 Link: https://www.summitracing.com/parts/lng-53000

I'm not going to order for a while, so more opinions would be appreciated.

Thanks,

[Daryl DeArman]

I would be inclined to look at a digital lab or test-grade gauge with suitable specs and then buy the cheapest analog gauge I could find with the hose length, bleed port and chuck style I want. Put the two together and have a gauge that suits my needs.

If you want to google accuracy requirements 3A and 3AR are .25% of reading and span. 4A and 4AR are .1%

[DaveW]

Thanks, Daryl,

I want a durable, accurate digital gauge. Within reason, cost is not too important.

I don't think combining gauges like you suggested would be less expensive, more accurate and more durable than a good Longacre gauge that has been proven in the field. Accuracy might be better with a lab gauge, but I don't need more accuracy than the gauge I mentioned. And I'd wonder about the durability.

[Daryl DeArman]

Thanks, Daryl,

I want a durable, accurate digital gauge. Within reason, cost is not too important.

I don't think combining gauges like you suggested would be less expensive, more accurate and more durable than a good Longacre gauge that has been proven in the field. Accuracy might be better with a lab gauge, but I don't need more accuracy than the gauge I mentioned. And I'd wonder about the durability.

I agree about the value:accuracy:durability of the Longacre mentioned. I thought you were looking for more accuracy than what the Longacre provided (I misread your requirements). I was able to get a rubber shock sleeve for my lab-grade pressure gauge, similar to this:

https://www.amazon.com/Accugage-Rubb.../dp/B0012TYTH8

Less than .1psi error at 40psi can be had for another $50-60.

[DaveW]

I agree about the value:accuracy:durability of the Longacre mentioned. I thought you were looking for more accuracy than what the Longacre provided (I misread your requirements). I was able to get a rubber shock sleeve for my lab-grade pressure gauge, similar to this:

https://www.amazon.com/Accugage-Rubb.../dp/B0012TYTH8

Less than .1psi error at 40psi can be had for another $50-60.

Thanks.

I don't need, or would really benefit from, more accuracy than the Longacre 52-53000 gauge has. If I knew more accurately than a half psi what my pressures should be set to, then I might want more accuracy. What I really need is repeatability and durability with the accuracy I mentioned in the 1st post. No matter what, it'll be much better than my current analog gauge which has some slop/bounce in the mechanism and is hard to read within 1/4 psi at best.

[GraemeD]

Alfano Tyre Control,

i have the temp version and love it for a "one man band" operation. Jump out of the car, take pressure & temps in less that 1 min. Look at them later after the suit & helmet are off.

https://www.alfano.co.uk/tyre_control.htm

[924RACR]

I'm leaning towards the Longacre # 52-53000 60-psi digital gauge. It has very good specs...

I've been using one of these (perhaps an older version, similar specs) for a long time... probably 12+ years. Replaced an analog Longacre gauge which we were stupid with and dropped one too many times. I love the fact that it zeroes before use. I also love the resolution (though it's fun sometimes to argue with door-slammer guys about needing that level of precision - note that I picked it up when I was still racing just the ITB car...)

Dislikes: don't leave it face-up in the sun, the LCD will go full black until it cools down. Not a big deal. Also, and this may be consistent with other gauges too, I notice a variation as the gauge "warms up" and the reading drifts. I will work around the car, set pressures, then make a second lap and adjust again bleeding off another 1/2 lb until they stabilize at the desired pressure. Like it needs a minute for the sensor etc to warm up and be repeatable. A bit weird, but manageable once you work with it.

[RussMcB]

<snip> I will work around the car, set pressures, then make a second lap and adjust again bleeding off another 1/2 lb until they stabilize at the desired pressure. Like it needs a minute for the sensor etc to warm up and be repeatable. A bit weird, but manageable once you work with it.

Vaughan, I *think* that is just the air pressure in the tires normalizing, not an issue with the gauge.

[924RACR]

No, literally, like I do laps *walking around the car* and watch the pressure reading change. Upward. Sorry, I wasn't clear these were not laps on track.

Once it stops, and I stop bleeding off pressure, we're good.

Usually by the time I finish setting the fourth tire (lap 1), the gauge reading is stable, and I just have to bleed the other three down in progressively smaller increments until the reading doesn't change.

[DaveW]

No, literally, like I do laps *walking around the car* and watch the pressure reading change. Upward. Sorry, I wasn't clear these were not laps on track.

Once it stops, and I stop bleeding off pressure, we're good.

Usually by the time I finish setting the fourth tire (lap 1), the gauge reading is stable, and I just have to bleed the other three down in progressively smaller increments until the reading doesn't change.

Unless I'm misunderstanding what you meant, bleeding off tire pressure will, every time, cause the pressure to then rise a small amount from where you left it. This occurs because the tire air cools when it expands as you bleed (Ideal Gas Law). It will then absorb heat from the tire and wheel which have not cooled, and regain a bit of pressure. Happens with any type of gauge.

[DaveW]

Alfano Tyre Control,

i have the temp version and love it for a "one man band" operation. Jump out of the car, take pressure & temps in less that 1 min. Look at them later after the suit & helmet are off.

https://www.alfano.co.uk/tyre_control.htm

Thanks.

Looks like a very nice unit, but it's ~$100 over my budgeted amount, and really more bells & whistles than I need.

[924RACR]

Unless I'm misunderstanding what you meant, bleeding off tire pressure will, every time, cause the pressure to then rise a small amount from where you left it. This occurs because the tire air cools when it expands as you bleed (Boyle's Law). It will then absorb heat from the tire which has not cooled, and regain a bit of pressure. Happens with any type of gauge.

Over the course of a minute or two? From dropping pressure by perhaps 4psi at most... and at ambient temps (60-80F, not on-track temps)... I mean, you're not wrong about the thermodynamics, but my gut tells me the deltas are too small to account for the variation I see, which is around 1psi high...

I mean, either way we arrive at the same answer, a consistent result... would love to believe it's not my gauge, but... pretty sure I get the same kind of variation even without changing pressures...

[DaveW]

Unless I'm misunderstanding what you meant, bleeding off tire pressure will, every time, cause the pressure to then rise a small amount from where you left it. This occurs because the tire air cools when it expands as you bleed (Ideal Gas Law). It will then absorb heat from the tire which has not cooled, and regain a bit of pressure. Happens with any type of gauge.

Over the course of a minute or two? From dropping pressure by perhaps 4psi at most... and at ambient temps (60-80F, not on-track temps)... I mean, you're not wrong about the thermodynamics, but my gut tells me the deltas are too small to account for the variation I see, which is around 1psi high...

I mean, either way we arrive at the same answer, a consistent result... would love to believe it's not my gauge, but... pretty sure I get the same kind of variation even without changing pressures...

Yes in the course of a minute or 2 it will do that. To avoid the issue, I preset the pressures before final setting to only 1/2 psi or so over what I want at the end. Any more than that, and I see exactly what you are describing.

Ideal Gas Law:
The ideal gas law, also called the general gas equation, is the equation of state of a hypothetical ideal gas. It is a good approximation of the behavior of many gases under many conditions, although it has several limitations.

The ideal gas law is often written as:

PV=nRT, where P, V and T are the absolute pressure, volume, and absolute temperature; n is the number of moles of gas; and R is the ideal gas constant. It is the same for all gases.

Link to calculation: https://www.ajdesigner.com/idealgas/index.php

[RussMcB]

Hopefully someone who's knowledgeable can chime in. I can be wrong about the cause, but for years I've gone around the car twice letting air out and it pretty much always takes a second bleed the second time around. I thought it was related to cooling while expanding, then the temp normalizes and raises the pressure a small bit.

[DaveW]

Hopefully someone who's knowledgeable can chime in. I can be wrong about the cause, but for years I've gone around the car twice letting air out and it pretty much always takes a second bleed the second time around. I thought it was related to cooling while expanding, then the temp normalizes and raises the pressure a small bit.

My "chime in"...
Exactly what I said above (posts 23 & 26).

[924RACR]

Then maybe part of my problem is not having a more accurate gauge prior, this being my first gauge that'd actually be good enough to identify the problem!

That, plus the fact I'm still using it nearly 15 years later, sounds like a good recommendation...

[DaveW]

Yes in the course of a minute or 2 it will do that. To avoid the issue, I preset the pressures before final setting to only 1/2 psi or so over what I want at the end. Any more than that, and I see exactly what you are describing...

IIRC, a 2 psi bleed results in ~ a 1/4 to 1/2 psi pressure recovery. And it also works in reverse - if you inflate by 10 psi, you'll see about a 1 to 2 psi drop-off as the tire air cools to ambient. That's from memory and my old not-so-precise analog gauge...

[DaveW]

...Longacre # 52-53000 60-psi digital gauge. It has very good specs:

Air pressure release button - Dual bleed buttons for even faster setting at lower pressures
External gauge bumper
Auto Off feature to save battery
17" hose with angle chuck - also includes ball chuck
Includes silver carrying case
User replaceable AAA batteries (2) included
0-60 psi with 0.1 psi increments
Accuracy: 0.3% (i.e., 0.1 psi @ 30 psi, 0.2 psi @ 60 psi)

Available at Summit Racing for $132.99 Link: https://www.summitracing.com/parts/lng-53000

Ordered today. Should have it tomorrow. Free shipping. With tax, $141.97.

Thanks, everyone, for your opinions!

[jpetillo]

I used an Accutire like Brian showed for about 10 years when doing motorcycle racing/trackdays. I would test against other people with the higher priced gauges. It was a great gauge - loved the reading down to 0.01, and very repeatable. The hose finally gave up the ghost.

I now use the Longacre # 52-53003 that I bought from http://www.advantagemotorsports.com and I find it very fast to turn on and come up. It always compares well with other Longacre gauges I've tested against. John

[DaveW]

I compared readings from my 5 tire pressure gauges, including the Longacre 52-53000 I just bought. The Ashcroft is a lab quality gauge I bought 20+ years ago, mated to another gauge's hose and end fitting and have been using since I got it. None of them was hugely off from the others especially considering their ranges.

In particular, the Ashcroft is pretty accurate, but my main issue with it was that reading it within its accuracy (it has 1/2-psi hash marks) was difficult, especially when one was rushing; 1/4-to-1/2-psi misreads were hard to avoid. Reading the RaceQuip was even more difficult since it has only 1-psi hash-marks. New results in post 71. Link to post: https://www.apexspeed.com/forums/sho...l=1#post648605

[t walgamuth]

It would seem to me that some of the bleed off need is caused by heat transferring from hot metal parts into the air. The dense metal will store a lot of heat energy compared to the less dense air so a little transfer will make a difference.

This is all great info about the gauges. Thanks very much! I guess nobody likes the old mechanical gauges...?

[DaveW]

Thought you might be interested in this issue I had on my Longacre #52-53000 0-60-psi gauge starting last fall.

The zero point kept bouncing between zero & 1 psi and zeroing did no good. The 2 AAA batteries looked perfect & tested 1.52 & 1.53V on a VOM. The low-battery symbol never appeared on the gauge. Battery contacts were perfectly clean.

I was about to send the gauge back to be repaired, but then as a last resort, I replaced the supposedly good old batteries with new batteries & the issue disappeared. Apparently one of the old batteries had too much internal resistance in spite of testing OK for voltage and that caused the issue.

See next post...the above conclusion was wrong.

[DaveW]

I bought that 60-psi Longacre gauge thinking it would be more accurate and repeatable than my best 30-psi analog gauge that has a really good scientific gauge head. In warm weather, the Longacre is usually quite good.

However, in cool (below 70F) weather because, according to Longacre the case is too tight and presses against the electronics, the zero randomly shifts by up to 3/4 psi. That means it's no better and sometimes less repeatable than my VERY good analog gauge. As a result, I only use the Longacre on my street vehicles for pressures above 30-psi. It's fine for that.

I went through a bunch of modifications to its internals that Longacre suggested, and while those seemed to help a bit, I no longer trust it to be as repeatable as I want. Unfortunately, I never used it within a year of purchasing it (2018 WG wreck, etc.), so the warranty had expired.

YMMV

[DaveW]

I bought that 60-psi Longacre gauge thinking it would be more accurate and repeatable than my best 30-psi analog gauge that has a really good scientific gauge head. In warm weather, the Longacre is usually quite good.

However, in cool (below 70F) weather because, according to Longacre the case is too tight and presses against the electronics, the zero randomly shifts by up to 3/4 psi. That means it's no better and sometimes less repeatable than my VERY good analog gauge. As a result, I only use the Longacre on my street vehicles for pressures above 30-psi. It's fine for that.

I went through a bunch of modifications to its internals that Longacre suggested, and while those seemed to help a bit, I no longer trust it to be as repeatable as I want. Unfortunately, I never used it within a year of purchasing it (2018 WG wreck, etc.), so the warranty had expired.

YMMV

I emailed Longacre again to update them on this issue - it'll be interesting to see what they say.

[SteveG]

In general, fluid (air is a fluid) pressure sensors whether analog or digital are designed and calibrated @ mid-range pressure @ 23 degrees C. Outside of these ranges you will see a reading error, the size of the error will be dependent on the sensor type. Analog gauges suffer less temperature effects and more pressure range errors, 50% outside of the middle will be off. Digital sensors suffer more from temperature effects because there are other components surrounding the sensor that cause error with temperature. Depending on the design and cost a digital tire pressure gauge will be inaccurate outside of 12 and 35 degrees C. This is the temperature of the gauge not the tire, if you warm or cool the gauge in your armpit, it will be more better.
Having designed and calibrated many commercial digital pressure sensors, I always use high quality analog tire pressure gauges such as Longacre. I use a 60psi gauge for spec Miata (26 psi cold target) and a 30 psi gauge for real race cars (14-16psi cold target).

Steve

P.S. For race tires ALWAYS use YOUR gauge for YOUR tires before you leave for pre-grid and for pit lane pressure checks. Swapping pressure gauges is an excellent rabbit hole to go down.

[mark elder]

I have had this for the last ten years. Absolutely reliable, I would buy another in a heart beat.
No memory features but I doubt if I would use then anyway: if I set the pressure cold I use the 'book' and when they are hot I tend to set them all equal. If I am aiming for 20psi, then I can usually remember that as I walk around the car.
Note currently out of stock on Amazon. But their reviews are all good.

Intercomp Tire Pressure Gauge, 0-99 psi, Digital, 1/10 lb Increments, Case Included, Each (360045)

[DaveW]

In general, fluid (air is a fluid) pressure sensors whether analog or digital are designed and calibrated @ mid-range pressure @ 23 degrees C. Outside of these ranges you will see a reading error, the size of the error will be dependent on the sensor type. Analog gauges suffer less temperature effects and more pressure range errors, 50% outside of the middle will be off. Digital sensors suffer more from temperature effects because there are other components surrounding the sensor that cause error with temperature. Depending on the design and cost a digital tire pressure gauge will be inaccurate outside of 12 and 35 degrees C. This is the temperature of the gauge not the tire, if you warm or cool the gauge in your armpit, it will be more better.
Having designed and calibrated many commercial digital pressure sensors, I always use high quality analog tire pressure gauges such as Longacre. I use a 60psi gauge for spec Miata (26 psi cold target) and a 30 psi gauge for real race cars (14-16psi cold target).

Steve

P.S. For race tires ALWAYS use YOUR gauge for YOUR tires before you leave for pre-grid and for pit lane pressure checks. Swapping pressure gauges is an excellent rabbit hole to go down.

If it were just inaccurate but repeatable at some low/high temperatures, I could understand that. But that's not the issue - it's the random zero point shift that even after multiple re-zeroings never settles down. I can't (won't) tolerate that issue. So, as you said, 30-psi Ashcroft scientific analog gauge it is.