I did almost the same thing. I had several pencil type of gauges and I got rid of the ones that didn't have consistent readability and/or read waaaay off(+/-) of the others. Now, I'm down to 4(1 for each car & 1 for the garage). I had the digital ones but, they kept on breaking and I became to anal with them.
Share your personal tire psi vs the recomemded
- Thread starter 1978elcamino
- Start date
- Status
Originally Posted by RayCJ
... What really complicates this, is that air pressure gauges typically are neither precise or accurate. The electronic type operate with internal pressure tranducers, based on strain gauges. Traditional dial types use calibrated springs. When either of those devices are stored in a hot (or cold) glovebox, their overall performance will fluctuate.
I have about 4-5 different pressure gauges and only 2 give generally the same reading under similar conditions. I had more of them laying around but, threw-out the ones that didn't give consistent readings or, were more than 4 PSI off from all the others. The ones that (I think) give good readings are the old-fashioned dial types made by Vondior. All the pencil types with the ejecting scale were junk. The "battery" powered ones seemed to be nothing more than a receptacle that held dead batteries.
… Anyhow, it adds a new perspective over this bickering about who puts how much air in their tires, and why.
Originally Posted by Char Baby
I did almost the same thing. I had several pencil type of gauges and I got rid of the ones that didn't have consistent readability and/or read waaaay off(+/-) of the others. Now, I'm down to 4(1 for each car & 1 for the garage). I had the digital ones but, they kept on breaking and I became to anal with them.
Well Char Baby, my engineering genes kicked in a long time ago. I was curious about how much the pressure varied in these things and did a bunch of simple tests. I tested them against each-other and also tried leaving some in a hot glovebox while letting others temperature-stabilize inside a refrigerator. [Of course, I reversed the sample groups and tested each in the opposite condition]. The units themselves gave very different results between hot & cold.
I'll take a half-educated guess and estimate that 1 out of 3 people who actually check their air pressure, are within +/- 2 psi of what they think. The rest are likely off by more than 2 psi. In cases when the air gauge does not read the same on the same tire 3 times in row, well... LOL, the reading is just a ballpark notion.
While I've not done tests on linearity, you can take bets that readings are non linear. I'm guessing that at the low and high end of their scale, they're off by much larger amounts.
FWIW, lab quality pressure gauges cost big bucks; on the order of 2 grand for NIST traceable, data-logging types.
In general, tire pressure readings are very rough estimates.
EDIT: Here are the Vondior units I have that seem to work fairly well. I have 2 units purchased a couple years apart from from each-other. They track very closely. https://www.amazon.com/Vondior-Tire...;qid=1567337376&s=gateway&sr=8-4
I also have a couple Victor brand gauges that are about 30 years old. You can't get them anymore as far as I know. They track closely with the Vondior units.
... What really complicates this, is that air pressure gauges typically are neither precise or accurate. The electronic type operate with internal pressure tranducers, based on strain gauges. Traditional dial types use calibrated springs. When either of those devices are stored in a hot (or cold) glovebox, their overall performance will fluctuate.
I have about 4-5 different pressure gauges and only 2 give generally the same reading under similar conditions. I had more of them laying around but, threw-out the ones that didn't give consistent readings or, were more than 4 PSI off from all the others. The ones that (I think) give good readings are the old-fashioned dial types made by Vondior. All the pencil types with the ejecting scale were junk. The "battery" powered ones seemed to be nothing more than a receptacle that held dead batteries.
… Anyhow, it adds a new perspective over this bickering about who puts how much air in their tires, and why.
Originally Posted by Char Baby
I did almost the same thing. I had several pencil type of gauges and I got rid of the ones that didn't have consistent readability and/or read waaaay off(+/-) of the others. Now, I'm down to 4(1 for each car & 1 for the garage). I had the digital ones but, they kept on breaking and I became to anal with them.
Well Char Baby, my engineering genes kicked in a long time ago. I was curious about how much the pressure varied in these things and did a bunch of simple tests. I tested them against each-other and also tried leaving some in a hot glovebox while letting others temperature-stabilize inside a refrigerator. [Of course, I reversed the sample groups and tested each in the opposite condition]. The units themselves gave very different results between hot & cold.
I'll take a half-educated guess and estimate that 1 out of 3 people who actually check their air pressure, are within +/- 2 psi of what they think. The rest are likely off by more than 2 psi. In cases when the air gauge does not read the same on the same tire 3 times in row, well... LOL, the reading is just a ballpark notion.
While I've not done tests on linearity, you can take bets that readings are non linear. I'm guessing that at the low and high end of their scale, they're off by much larger amounts.
FWIW, lab quality pressure gauges cost big bucks; on the order of 2 grand for NIST traceable, data-logging types.
In general, tire pressure readings are very rough estimates.
EDIT: Here are the Vondior units I have that seem to work fairly well. I have 2 units purchased a couple years apart from from each-other. They track very closely. https://www.amazon.com/Vondior-Tire...;qid=1567337376&s=gateway&sr=8-4
I also have a couple Victor brand gauges that are about 30 years old. You can't get them anymore as far as I know. They track closely with the Vondior units.
Last edited:
Yup, in one way or another I've done many similar comparisons & test with my tire gauges over the past 5-6 decades. I also use my butt dyno to gauge on comfort/quiet & harshness/smoothness of my tires.
And as long as the tires are within a couple of psi of the tire place card in the door jamb, I sleep well. This is not to say that during certain circumstances that I don't stray slightly away from what I have mentioned. However, I am quite consistent with what & how I read my tire psi.
And as long as the tires are within a couple of psi of the tire place card in the door jamb, I sleep well. This is not to say that during certain circumstances that I don't stray slightly away from what I have mentioned. However, I am quite consistent with what & how I read my tire psi.
Originally Posted by Char Baby
Yup, in one way or another I've done many similar comparisons & test with my tire gauges over the past 5-6 decades. I also use my butt dyno to gauge on comfort/quiet & harshness/smoothness of my tires.
And as long as the tires are within a couple of psi of the tire place card in the door jamb, I sleep well. This is not to say that during certain circumstances that I don't stray slightly away from what I have mentioned. However, I am quite consistent with what & how I read my tire psi.
Yup! Same here. I finally settled on some gauges that seem to read consistently. I've spent my fair share of time on 1/4 mile strips, road tracks, and daily commuting in cars and motorcycles. I go by how the tires are performing.
Yup, in one way or another I've done many similar comparisons & test with my tire gauges over the past 5-6 decades. I also use my butt dyno to gauge on comfort/quiet & harshness/smoothness of my tires.
And as long as the tires are within a couple of psi of the tire place card in the door jamb, I sleep well. This is not to say that during certain circumstances that I don't stray slightly away from what I have mentioned. However, I am quite consistent with what & how I read my tire psi.
Yup! Same here. I finally settled on some gauges that seem to read consistently. I've spent my fair share of time on 1/4 mile strips, road tracks, and daily commuting in cars and motorcycles. I go by how the tires are performing.
Right!
I also keep'em rotated and give'em a good visual inspection while doing so. This does indeed tell you a lot.
I also keep'em rotated and give'em a good visual inspection while doing so. This does indeed tell you a lot.
Last edited:
This is the pressure gauge that I use. It stays within 1 psi of the liquid filled gauge on my tank.
https://www.summitracing.com/parts/kti-89001
https://www.summitracing.com/parts/kti-89001
No need to throw out pencil type gauges as they can be adjusted provided they produce repeatable readings.
They work by extending a coil spring and that spring has an adjustable anchor at one end which changes the number of active coils and therefore the spring rate. Just unscrew the head and the adjustment will be visible.
They work by extending a coil spring and that spring has an adjustable anchor at one end which changes the number of active coils and therefore the spring rate. Just unscrew the head and the adjustment will be visible.
Additional door sticker next to the standard tire pressure sticker on my 17 Continental says add 4 PSI if driving over 100 mph.
I run 5 psi below the max of the tire say the max is 45 i run 40.
Fun thread to read.
40 years ago in autocross on bias ply tires we ran 50-60 psi in tires rated for 32. Never an issue, tires held up fine on most cars.
Fast forward to today and my Pilot Sport 4S's are rated at 50 psi max. Due to size my vehicle specs 32 psi cold for a 275/35/20 tire on a 4000 pound car. This car is a bit different from many in that it is truly ready to track right out of the box.
When it visited Homestead and ran 160+ around the big oval I ran 32, today I might run 34 but more pressure on my ride just rounds the contact patch and reduces traction
40 years ago in autocross on bias ply tires we ran 50-60 psi in tires rated for 32. Never an issue, tires held up fine on most cars.
Fast forward to today and my Pilot Sport 4S's are rated at 50 psi max. Due to size my vehicle specs 32 psi cold for a 275/35/20 tire on a 4000 pound car. This car is a bit different from many in that it is truly ready to track right out of the box.
When it visited Homestead and ran 160+ around the big oval I ran 32, today I might run 34 but more pressure on my ride just rounds the contact patch and reduces traction
Door decal 30psi.
On a front wheel drive car I put:
38 in the front
36 in the back
On a front wheel drive car I put:
38 in the front
36 in the back
Duplicate post that it won't let me delete.
Last edited:
- Status
