Check your Tire Gauge!!!!

I feel like we all try to help each other out here. I am going to pass along a tip you have probably heard 50-times and thought it doesn't apply to me.

CHECK YOU TIRE GAUGE AGAINST A KNOWN QUALITY GAUGE!!

We have been having some tire spinning issues this year ever since Tulsa. We finally eliminated all other things and checked the gauge at someone else's insistence. It was 1.25-1.5 lbs off when checking it against a correct gauge. So when we put 5.5-lbs of air in our tires, we were putting 6.75-7.0 pounds of air in them.

Do yourself a favor and check your tire gauge this week.

Rapid

 

it does not matter what some elses gauge says,use yours always,unless you a trying to run what the other guy runs,we all know that don't work!his 5.5 lbs is not on the same car,tire,wheel.......as yours if the car works with 100 psi on your gauge run it!

 

I now feel 20% dumber after reading this post.

 

Mcfly,

That is true. But follow along for a second.

#1. Don't just check it against someone else's gauge. Check it against a standardized-calibrated gauge. I believe the tire guys all have one at the events. Just because your neighbors gauge is different, doesn't make his right unless it was just checked.

#2. If you don't know exactly what you are putting in your tires you have no way to come back to a baseline when the car stops working.

No one likes to put "hey we were screwing up" posts out here. I am trying to save someone else the problems we faced.

Using our car as an example. Last year it went down the track every time. 1st race of the year at Tulsa, #1 qualifier off the trailer in the first session, and a Runner-up. After that race, nearly every pass was spinning the tires 10-30 feet off the line no matter what we tried. We made no changes to the car. Same tire pressure as always. Now we discover the gauge malfunction, correct for it and the car is going down the track better again. Without finding the gauge problem we would be throwing parts and changing things to correct a problem it didn't have.

Rapid

 

Randy, thanks for the heads up!!!!

 

we have all heard stories about torque wrenches that have gone soft doing a similar sort of thing. The moral of the story is calibration.

 

i have to add my story here. we have been using an old TAVIA tire gauge for the past 5 years with no problem.....ever. it's one of those $25 ones you get from jegs. at our last race we had a major problem, the car would go about 100 feet and take a sharp right. this car goes straight 90% of the time. next qualifying session we were in the other lane, same thing. tires checked same on gauge after each run. i even measured the circumfrence, and it was within 1/8". i had a crew guy borrow a gauge from a guy next to us. one tire checked 4.5, the other was 6! i guess the hose was breaking down inside, and if you turned it one way it would check different. you see almost everyone double up the hose and put the gauge in their back pocket, it's just a habit i guess. DON'T DO THAT. it could cost you down the road, and you might find out the hard way like we did.

 

Check them often. Especially if you have someone check the pressure for you and you run tubes and liners. How many times has the low pressure guage been pegged when mistakenly put on the tube instead of the tire?

 

That never happens.................yeah right. I don't have enough fingers to count how many times I've done that. It's amazing how many things we take for granted.

 

I used to have a gauge that if you checked the tires 3-4 times in a row youd get 3-4 different answers. Gauges do wear out.

 

Great thread Rapid.
Thanks for sharing.

 

Great post, Randy. Last year we had aquired a liquid-filled gauge. It supposedly would make the needle movement smooth and accurate. I would set the tire pressures in the pits, then put the gauge in the tool tray when we were ready to tow the car to the line. I would check the pressures again just before the run to find that the tire pressures were as much as 1-1/2 lbs higher. I figured that the sun was heating the tires while in the lanes, increasing the pressure in the tires. I would drop the pressures back down. During the turnaround, I would check the pressures again to find that the pressure was as much as 1-1/2 lbs low, again thinking that the lack of sun being next to the trailer and under the awning allowed the tires to cool, lowering the pressure (make sense?). So I would service the tires back to our running pressures. This happened several times before I realized that what the pressure gauge was doing was while it was in the tool tray in the sun at the lanes, the liquid inside the gauge would warm up and the pressure within the gauge would change. The zero point would now read 1-1/2 lbs. When in the shade of the trailer, or in the dually, the zero point would be zero. We were actually running the tires at a lower pressure than we thought we had set and the car was having a serious shake problem (we were also having clutch issues, which is another story). The moral; don't keep your liquid-filled gauge in the sun, or just s#%tcan it like we did ours. Also, have your gauge checked against a known good gauge or a calibrated source.

 

There are some good tips in here. Thanks for posting them.

Rapid

 

Was in the lanes next to a guy in a nostalgia f/c and I noticed his tires looked VERY soft. He said he just set them to 6psi. I told him to try another gauge and offered mine. Turns out he only had 2.5psi in his tires!!! That would have been an interesting ride. I agree... its the little things that we always take for granted but they can still kick your butt all the same. I also think any experienced racer should visually know the difference of what a tire looks like with only 2.5psi in it and see something is not right. The driver, sitting in the car, assumed his crew had the tire pressure set for the run. Racing... where assumtions can cost you everything!!!! EVERYTHING wears out... period... no matter the cost. Check everything... twice if needed.

-Doug Nordberg