recomendations, suggestions, places to buy, places to avoid? all help is much appreciated thanks

 

Whats the question?

You want a probe-type for tires.

 

You can get a cheap pyrometer from HF, I paid $50. Or you can spend almost $200 for more reliable brands.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by El Pollo Diablo &raquo;</TD></TR><TR><TD CLASS="quote">Whats the question?

You want a probe-type for tires.</TD></TR></TABLE>

just wondering what are some good brands and where's the best place to find them

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">you can get a cheap pyrometer from HF, I paid $50. Or you can spend almost $200 for more reliable brands.</TD></TR></TABLE>

what's hf?

 

https://honda-tech.com/zerosearch

 

You can use either a probe tye for race tires or an infrared for both tires and other things (like header temperatures or brake temps). Both types will work on tires with this warning-the probe is much more accurate since it is reading the carcass temp and not the surface which cools more rapidly.
Where to buy-Longacre, Sears, Harbor Freight and a host of others. We use a Craftsman infrared with our Azenis for track days and Time Trials. Price is around $100. Temp range is up to you, but I would recommend that you go for one that reads higher than 500 degrees.

 

there is longacre, and the tif 7000 series. thoses are the ones i have.

 

I have heard that there is great difference in temp reading from probe type to the infrared type. Anyone able to prove or disprove this? Or have any experience with both?

 

Yes, a probe-type gives a much more reliable reading, especially for tires.

 

Probe type is more accurate, that's why you see them in pro racing.
Infrared is close enough, food industry uses it.
HF is Harbor Freight.

 

Close enough for what?

I would use an infrared one on headers and such, but I wouldn't use it on tires.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by El Pollo Diablo &raquo;</TD></TR><TR><TD CLASS="quote">Yes, a probe-type gives a much more reliable reading, especially for tires.</TD></TR></TABLE>
The Devil Chicken is right, probes are better for tires as they reach into the carcass to get the temp and aren't just reading the very surface temp. I did borrow an infrared to tell how hot my radiator and hoses were with my cooling problem. My probe unit was about $80 a decade ago but I don't think it is on the market. It is a battery eater, probably becasue I use it so rarely (use it a lot when I race, I just race too rarely).

 

Not only is a probe better, but a longer probe is better-better. You want to really get down into the rubber - like on an angle with a 3/8" probe, depending on what kind of tires you have.

K

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRX Lee &raquo;</TD></TR><TR><TD CLASS="quote">
The Devil Chicken is right, probes are better for tires as they reach into the carcass to get the temp and aren't just reading the very surface temp. I did borrow an infrared to tell how hot my radiator and hoses were with my cooling problem. My probe unit was about $80 a decade ago but I don't think it is on the market. It is a battery eater, probably becasue I use it so rarely (use it a lot when I race, I just race too rarely).</TD></TR></TABLE>

Let's discuss this more thoroughly (ie: I have more questions).

Something I am running into with trying to tune via the pyrometer is the chance of false readings in the pits. Every time I think I know something, it gets discounted due to the time it takes to bring the car into the pits to take a reading. As an example (numbers pulled out of thin air, but pretty accurate):

Road Atlanta
out middle inside ......... inside middle out
LF 175 183 190 ........ 190 185 175 RF

LR 175 180 185 ........ 170 160 140 RR

I looked at these temps, combined with the car being loose in left hand turns, and decided that I needed less negative camber in the RR.

But when I mentioned this, it was discounted due to there only being 3 real left hand turns, and the ones that would be taken hard before the checker are a over a mile from the pits.

The theory told to me was that the outside edges of the tires cool off at a faster rate on the cool-down lap due to air flowing over them and not touching the ground much on the straights because of negative camber. I can see this working and being true, and therefore I am not too worried about the other tires as ~10 degrees seems reasonable, but the RR has a bigger spread. (But it has the most time to cool, but the camber is the same on both rears.) This is using a probe type pyrometer, going in at an angle as deep as possible.

I am thoroughly confused over this. At this time, I am leaning toward taking camber out of the RR anyway, just to see for myself what happens. I would hate to waste a session if it makes things worse, however. There is no way for me to get time on a skid pad, so I can't test it that way.

Anyone have a clue?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RacerBowie &raquo;</TD></TR><TR><TD CLASS="quote">
At this time, I am leaning toward taking camber out of the RR anyway, just to see for myself what happens.</TD></TR></TABLE>

I think the cooling and limited number of left turn comments is a likely valid one and one can make a case either way. On one hand reducing RR camber might make it even looser yet but it also runs the chance of putting more tire on the ground for more grip. The only way to test it is to try it and see for yourself. Is there a gain, a loss or no difference? I don't know how much nagative camber you run but if you make a notable but not too whopping change then you could see what it does in the target corners but also if it has effect in other corners too and if any gain outweighs any loss. I doubt any change is going to make such a drastic difference that is wastes a session for you. My vote is to go ahead and test your theory as it could go either way and you'll never know without doing it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRX Lee &raquo;</TD></TR><TR><TD CLASS="quote">

I think the cooling and limited number of left turn comments is a likely valid one and one can make a case either way. On one hand reducing RR camber might make it even looser yet but it also runs the chance of putting more tire on the ground for more grip. The only way to test it is to try it and see for yourself. Is there a gain, a loss or no difference? I don't know how much nagative camber you run but if you make a notable but not too whopping change then you could see what it does in the target corners but also if it has effect in other corners too and if any gain outweighs any loss. I doubt any change is going to make such a drastic difference that is wastes a session for you. My vote is to go ahead and test your theory as it could go either way and you'll never know without doing it.</TD></TR></TABLE>

That is more or less the plan. Hopefully we will have a test session soon after repairing the car, and I will be able to experiment with a few things. We are just now becoming methodical with our testing and record-keeping, so I don't have any data to fall back on yet. We'll see I suppose.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by El Pollo Diablo &raquo;</TD></TR><TR><TD CLASS="quote">Close enough for what?

I would use an infrared one on headers and such, but I wouldn't use it on tires.</TD></TR></TABLE>
Close enough to give you an idea of surface temp.
You are right, for tyres you need probes to go deeper.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RacerBowie &raquo;</TD></TR><TR><TD CLASS="quote">the tires cool off at a faster rate on the cool-down lap</TD></TR></TABLE>
What we do is come in right after running some hot laps and there must be a minimum of about 5 minutes left in the session as well. Drive the car hard all the way to the white line on pit lane. (Shut the car off and put it in gear and don't touch the brakes while in the pits, obviously.) Then use the remaining few minutes of the session to go out and do one, or maybe two cool down laps. Most of the time when we plan to take temps, but somehow catch the checkered flag or really slow traffic, we abort taking temps since the tires would have been cooled off too much for reliable readings that can be compared with the others taken. However imo it would still be better doing it this way then not at all. The temps will be down all around, but if there is something significantly wrong with the temps, you'd still be able to pick up the difference even though diminished. Any idea when such a test session is in order for you?

 

Just to add to this-We are using the InfraRed for most things on the car including brake temps as that is an indicator of how hard I'm actually using them. I will agree that it is not a perfect or 'best' measurement for tires. Rather for the type of rubber and lack of negative camber, it is adequate for ocassional track useage. I can also say that our experience and setup has been pretty consistent at the 3 tracks we run.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hracer &raquo;</TD></TR><TR><TD CLASS="quote">
What we do is come in right after running some hot laps and there must be a minimum of about 5 minutes left in the session as well. Drive the car hard all the way to the white line on pit lane. (Shut the car off and put it in gear and don't touch the brakes while in the pits, obviously.) Then use the remaining few minutes of the session to go out and do one, or maybe two cool down laps. Most of the time when we plan to take temps, but somehow catch the checkered flag or really slow traffic, we abort taking temps since the tires would have been cooled off too much for reliable readings that can be compared with the others taken. However imo it would still be better doing it this way then not at all. The temps will be down all around, but if there is something significantly wrong with the temps, you'd still be able to pick up the difference even though diminished. Any idea when such a test session is in order for you? </TD></TR></TABLE>

Good ideas, thanks Alex!

As for a test session... I hope OPM is going to do something, but if not, I will either have to do a Rd. Atl. track day, a Seat time event at Roebling (sept 23 I think), a turn one track day at CMP, or something. Maybe I will rent out Little Talladega for a day, wanna come?