Pyrometer

[harry kaplun]

Just started using R compound tires for HPD events and am very impressed with the difference over street tires. These tires will wear quickly but I have been advised if you use a pyrometer to set the tire pressures it will extend the life of the tires materially.
Using the pyrometer each tire can then be set for the track and conditions that day. It makes sense.
Before I invest in a pyrometer, I'm curious if others use pyrometers to extend tire life and performance. If so which pyrometer do you use?

[No Doubt]

I have a memory Pyrometer (Accutech). You can get them at Longacre Racing.

And yes, they are most beneficial, especially when running R compound tires. They will definitely help extend tire life by enabling you to obtain accurate tire temps. R compound tires, such as Hoosiers for example, often benefit from a specific amount of negative camber for instance and running less than nominal will result in incresaed wear. Take at least three tire temps immediately after coming off the track: outside shoulder, center of tire and inside shoulder. Increased heat indicates increased load due to camber, toe, etc., but you probably already know that.

Having someone in the pit with the Pyrometer ready to go is helpful in order to obtain more suitable and accurate readings.

[harry kaplun]

Originally Posted by No Doubt

I have a memory Pyrometer (Accutech). You can get them at Longacre Racing.

And yes, they are most beneficial, especially when running R compound tires. They will definitely help extend tire life by enabling you to obtain accurate tire temps. R compound tires, such as Hoosiers for example, often benefit from a specific amount of negative camber for instance and running less than nominal will result in incresaed wear. Take at least three tire temps immediately after coming off the track: outside shoulder, center of tire and inside shoulder. Increased heat indicates increased load due to camber, toe, etc., but you probably already know that.

Having someone in the pit with the Pyrometer ready to go is helpful in order to obtain more suitable and accurate readings.

Thanks for the info and quick response.
Confirmed my thoughts

[DJWorm]

A tire pyrometer is essential if you are to get the maximum performance from your tires.

There are 3 basic types:
- Infrared indirect read.
- Surface contact thermometer
- Probe

The probe type is the ONLY one with reliable and accurate measurements. It is used by inserting the probe into the tire surface....say 1/16 - 1/8" deep. You should get a Probe Type Memory Pyrometer

Also it is vertually impossible to get accurate readings by yourself....ie stopping the car, getting out and doing the measurements yourself. You SHOULD use an assistant to take the readings immediatelyu sfter you stop.

The initial set up of the car should be done on a skid pad, one tire at a time. I.e.. Heat the tires to optimal temp, then 2 laps on the skid pad and measure one tire inside, mid and outside; then 2 more skid pad laps and measure the next tire position. If you measure all four tires at once, they cool too fast.

If you are measuring all 4 tires in the pits after a number of laps on a predominately right hand road course circuit measure Inside/Middle/Outside LF-RF-RR-LR; OR for left hand circuit, LF-LR-RR-RF. ALWAYS in that order and ALWAYS Inside/Middle/Outside. Consistancy

You might also consider getting a Durometer if you run multiple sets or are wondering if an older tire is suitable.

I also recommend Pro Blend Race Tire Cleaner and Pro Blend Hot Lap or Victory Lane tire prep.

Next post will expand on actually "reading" the tire.

[DJWorm]

1. Understand that tires are the most important part of a suspension. In fact they make up 80% of suspension preperation and performance. Everything else in the remaining 20%; shocks, springs, sway bars, alignment etc. is used to make the first 80% reach their potential.

2. The best source of information is reading. Hoosier, Goodyear and Kuhmo technical and spec papers. Carrol Smith books etc.

3. Next best source is race tire distributors such as Tom Reichel at Mid Atlantic motorsport (Hoosier)

4. Next source is more experiencied drivers and WINNERS in your class. I have found that they are generally very helpful. One Caveat: They will not give wrong info, they just might not give you ALL the info to protect their competitiveness.

5. A or Autocross compound (30-45) tires have a lower optimal operating temp. Get "stickier" sooner and cannot stand long periods of hiigh temps. Think of them as Indy qualifying tires. Usually the optimal temp is 110* - 140.
A compound can be used on a road course for short (<30 min sessions).
AutoX tires heat uip primarily due to surface friction from the OUTSIDE -> IN

6. R compound (30-40) tires have a higher operating temp 170* - 220* AND TAKE LONGER (2 LAPS TO REACH OPTIMAL TEMP. R compound tires heat from the INSIDE -> OUT due to tread deformation.

7. Regardless of the compound they are "read" the same. Tire tread temp correlate well with starting inflation pressure and initial camber setting. Ultimately the objective is to get the inside /mid outside temps equal across the tread face. Practically if they are within 10* they're perfect for AutoX whereas I would accept within 20* on a road course R compound.

Following these examples (A compound):
OUTER/MID/INNER temp readings

120/120/150 = Too much negative camber

150/120/120 = Not enough negative camper

150/110/150 = Under Inflated

110/150/110 = Over Inflated

114/116/118 = Perfect cold starting temp & Perfect negative camber

Pearls:
Although wider is usually better, IF an AutoX tire is too wide, it will NOT reach optimum temp during the short run