Tire Pyrometers

[Wooly]

It is time for a new tire pyrometer and I wanted to get some feedback on the new handheld inferred pyrometers available. Has anybody had good or bad experiences with them or is it still better to go with a direct contact model. Recommendations on brand and models appreciated.

Wooly
74 Zink Z10

[DaveW]

Infrared measures surface temperature only. Unless you are doing this in real time (on the track) these measurements are almost useless, since the surface temperature changes too rapidly to be meaningful. What you want to measure is under the tread surface next to the fabric to get an "average" over the last lap or at least the last few corners.

[Daryl DeArman]

Wooly,

As Dave mentioned you want to measure the temp under the surface. However, I have yet to find a probe unit that can take 12 readings without the temps falling/equalizing 5-10 degrees by the time I'm done. And that's waiting just a few seconds for each reading to semi-stabilize.
Plus as much as my cheap butt has to wear them down before I replace them, I'm afraid I'll puncture one.

I am sure they are out there, probably just a little out of my budget.

Let me know if you find something suitable.

How's the trailer working out?

[Larry]

The probe-type pyrometer is the ONLY way to go! Yes, while the tires cool rapidly, you can still get good information by checking your tires in the same sequence every time (e.g., RF, LF, LR, RR), and then comparing the readings to the same tire in previous sessions.

Larry Oliver
International Racing Products

[carnut169]

I purchased a Longacre Memory Pyrometer and it is pretty neat. It allows you to take 3 reading per tire quickly as it stores the temps for you. After you have all your readings you can go back and write them down, make changes, etc. I got mine on Ebay & I think it was about $100.

[Avon Racing Technical]

Just thought that I would add my two pence (cents) worth:-

In the main, consistency is the most important thing. It will be next to impossible to subject the tread surface to the same conditions each and every time you come into the pits, what with rain, red flags, other traffic etc. However, the very base of the tread is much less prone to these environmental changes and is therefore the best place to measure the temperature. If you do it in the exactly the same way each time, it does not really matter that it may not reflect the exact temperature you are trying to measure, but short of putting the tyre in laboratory, you will never be in a position to achieve this anyway. What you will be looking for are trends, both across the tread and around the car, so as long as the same person uses the same equipment in the same way, you should be able to spot set-up changes within your tyre temperatures.

I always start with the loaded front, then loaded rear, unloaded rear and finally unloaded front (as heat loss is proportional to temperature difference, it stands to reason that the hottest tyre will lose the most temperature in any given time)

An adjustable needle pyrometer set to about 12mm (say half an inch) going in at 45° to the tread surface has proved the most effective way of getting to the fabric below the tread without going into it. In taking many thousands of tyre temperatures over the years, I have not yet punctured one (tempting fate here I know). The only real risk of puncture comes when the car is suddenly raised or driven off, which only really affects teams with large numbers of people crawling all over them. The Longacre pyrometer is fine in use but does have a few problems; the supplied needle is not adjustable and if memory serves me god, way too short and it usually assumes that you want to take the tyre temperatures in a certain order (it hails from NASCAR use). As I recall, it also requires disassembly in order to change from °F to °C (although I don’t imagine that’s a huge problem in the States.) although I could be wrong.

There have been a number of previous posts on this subject, but I have no idea how to find them in the very short term.

Regards,

Pete.

[Todd TCE]

Reminds me of some effort put in my S3 Racing (Kent Stacy) some years back on FM; they did a great job of fitting 'active sensors' to the car via some bolt on IR sensors with bars to hold them. They managed to record on track temps in the data logger. I think the only problem they had with this was the sampling rate and storage of the data, if I recall it could be quite large.

And NO we did not let them run them in the race for safety reasons.