db2xpert

At the track today we happened to try four well known pressure gauges. No two were the same, with a difference of more than 3 lbs across the group.
We had gauges from Joe''s, Jegs, Longacre, and intercomp.
Plus a fifth simple truck type stick gauge.

None of these were high dollar items, all under $100.

Is there a reasonably priced gauge that is accurate? How do we know?

CAVEAT:
Of course if you are using the same gauge all the time, absolute accuracy is less important than consistency.

VetteDrmr

Out of curiosity, why do you care? Any advice we get on starting pressures is just to get us in the ballpark, then we adjust based on our experience. So, IMO, consistency *is* what is most important.

HTH, and have a good one,
Mike

c4cruiser

I have a Longacre analog-style gauge and I like it because of the 3" dial and the ability to drop pressure using a button on the gauge. The needle is very thin so I can "see" 1/2 lb increments. It also has a nice rubber cover so it can take being dropped.

I also have one of those cheap little pocket size analog gauges you can find on any chain parts store counter. IIRC, I got it in a goody bag at some car show a number of years ago. It is pound for pound as accurate as my Longacre $75 gauge. Go figure...

Gordy M

Danny Kellermeyer has run an alignment school from time to time and one of his modules is calibrating your tire gauge. He has a high dollar scientific gauge mounted and presurizes it to 35lbs. We all tested our gauges to that gauge and every one was off--both high and low. He tests his track gauges to the large gauge and marks the percentage difference. As I recall that gauge was several hundred dollars.

db2xpert

As I stated, if you use the same one all the time, with the same brand tires, it does not matter.

If I had one that I knew was accurate, I can easily calibrate the offsets of my other gauges to that.

If I change tire brands, and the recommended cold starting pressure is 25 i.e.... I'd like to be sure to start there vs. setting the pressure at 25 with a gauge that reads 3# high, so I'm really at 22#.

Quite simply, I want to have one gauge that IS accurate, after that the direct accuracy of others as I calibrate from that gauge doesn't matter. I don't need accuracy to .1 or .2#, but being off by 3# is not acceptable.

Bill32

If you were using tire temperatures to set your pressures, you could use a decent Longacre or Intercomp (and use the same one all season).

Doesn't matter if it reads a pound or so off because you're adjusting to those temperatures.

For your starting points, you should be checking your temperature/pressure logbook to see what the ambient and track temps were the last time you were at the track.

If you want to check your gauge, take it to a local welding supply that certifies gauges (many do this), they can check it for you.

sccaGT1racer

I use the longacre large display with the air bleed on it. Don't get all hung up on 3 psi between gauges. Get a quality gauge and use a log book for setups.

383

Good idea. just stop at your local Airgas and have them check it

acrace

I have a "reference gauge" that I compare my "track gauge" to, on a regular basis. This way, if anything happens to my "track gauge", I can catch it. I wasted two months, years ago, trying to figure out a handling problem when, in the end, my gauge had drifted off by 4 or so PSI.

Bill32

Yea, I've been going that for 20 years.

But, I'm not real concerned with what the pressures are after the initial setting in the a.m.
After that, I only use the gauge to raise/lower the pressure half a pound (or a pound, whatever) to adjust the temperatures.

This is all I really look at:

nolimits

I've used a small analog dial for years and it does vary against others a pound or two but is consistent at least. Here's another angle, what do you guys see comparing your gages to the DIC TPMS pressures? Do we think the TPMS is different or way off? This is just for discussion sake, preference always to a direct measurement at the tire w/o electronics unless you've got F1 sophistication... when it works!

sccaGT1racer

My 2008 c6 tpms readings are very close to the mechanical gauge but don't instantly update.

db2xpert

Thanks, I'll have them calibrated -

rfn026

Accuracy is not as important as reliability. You want the gauge to read exactly the same every time you use it.

The main point is to get a good gauge and use only that gauge. Do not swap gauges. That's where the trouble starts.

Here's an article I did a while back on gauges.

Richard Newton

Bill32

Great, then as said, only use one at the track.

Bill Dearborn

Get the gauges calibrated and they will all read about the same. However, the calibration is only good for a certain time period. On a mechanical gauge it probably needs to be calibrated every 6 months. Calibration doesn't necessarily mean knowing how far off the gauge reads. Some places adjust the gauge to make it read correctly for that 6 month period.

I think the most important things about gauges are relibility, consistency and ease of use. Ease of use usually means large easy to read numbers with 1 lb increment resolution at the minimum, bleed valves, pressure hold so you can read the measurement once the gauge is removed from the tire valve and a chuck that is easy to get and remove from the tire valves while sealing properly.

Bill

Feffman

Ditto here. Mine may be slightly updated as the face is luminescent for low light.

Feff

Charley Hoyt

I use a Longacre analog gauge wing a 4" dial that is accurate to .5% ( most others are 2%). Prior to that I had a very nice digital gauge from Griot's.... I liked that gauge a lot until the batteries died at the track. I will never get another gauge that needs batteries. If you want a great deal on Longacres gauges, check out their overstock catalog. You can save a lot if you don't care about having "this years" graphics.

http://www.longacreracing.com/Userfi...BC_catalog.pdf

Charley

383

Thats how i get all my stuff