I don't think that there are so many designs in NASCAR tires. But, there probably a great many compounds to make up the tire. One track, a little dash of this and a teaspoon of that.

wilmywood8455 - 12 March 2008 06:37 PM

stowaway - 12 March 2008 12:32 PM

F1 brakes need to be at over 1000° to work right. Teams WANT heat in them. They are carbon/carbon and literally wouldn't well work at the temps nascar cars see, even at the most demanding brake tracks. Lately teams have been making shields to keep the heat in the brakes. Temperatures are much more of a concern for F1 cars than Nascar.

Yes, carbon brakes do need to be hot in order to work; however:

The shields are NOT to keep heat in the brakes, they are to direct the cooling air exhaust where it can best benefit the overall aerodynamics of the car. Carbon brakes, having a much higher coefficient of friction than steel rotors and their corresponding pads, heat up much faster and also dissipate that heat faster as well. They are known for becoming red hot on corner entry and cooling right back off. Keeping them hot is not an issue, as far as I know.

This from Toyota's Dieter Gass:

"“The carbon brakes only work in the right temperature window - if you are below 300 degrees there is almost no braking at all so it is important to heat up the brakes. On the other hand, it is important not to have the temperature too high. This is why we have big cooling ducts on all four brakes. In this way the temperature is controlled and we have the optimum brake temperature for the optimum braking performance.” "
http://www.formula1.com/news/features/2007/8/6625.html

Granted, most brake cooling in F1 is to keep the caliper and therefore the fluid cool, but some cooling of the rotor surface is done as well for carbon, at least according to AP:

"Cooling Requirements
The uprights should be designed to provide a cooling air pathway of at least 140cm² area. AP Racing carbon/carbon requires good face cooling. It is worth monitoring airflow / temperature on both inside and outside disc faces during testing."
http://www.apracing.com/info/info.asp?section=Gt+&+Lmp+Brake+Carbon+User+Guide_51

I do not remember the last time (I heard of)an F1 car had brake overheating problems (or underheating problems); this happens regularly in Nascar especially at Martinsville, so I cannot agree with your assertion that "Temperatures are much more of a concern for F1 cars than Nascar."

Overheating and undercooling usually both happen at the canadian grand prix. Sometimes the brakes literally explode into powder. The long straights at the canadian GP overcool the brakes and when the teams fit smaller brake ducts to compensate the brakes would then sometimes over heat because they cant disapate the heat quickly enough.

[quote author="E46ZCP" date="1207138446

Overheating and undercooling usually both happen at the canadian grand prix. Sometimes the brakes literally explode into powder. The long straights at the canadian GP overcool the brakes and when the teams fit smaller brake ducts to compensate the brakes would then sometimes over heat because they cant disapate the heat quickly enough.

I'm sure you have some information/links on the heating/cooling issue and on the last time a brake rotor "exploded into powder" in F1 due to heat?

Australian GP, Mark Webber

Malaysian GP, Sebastian Vettel

Both had either a pad or rotor explode.

http://www.autosport.com/news/report.php/id/65760

stowaway - 02 April 2008 09:50 AM

Australian GP, Mark Webber

Malaysian GP, Sebastian Vettel

Both had either a pad or rotor explode.

http://www.autosport.com/news/report.php/id/65760

I don't think that's what they were looking for, since neither one seems to have occured due to excess heat. Webbers was during his first or second lap of Q3 and Vettels wasn't at race pace either. I could be wrong on Vettel, not sure.

Bill

NoviVespa3 - 21 March 2008 02:08 AM

hobbymanbill - 20 March 2008 11:43 PM

I'm pretty sure one thing you're NOT going to see anytime in the near future is ANYTHING of an electronic nature on a NASCAR stock car. They like their 1965 technology, and they are going to stick to it. Keep that kind of talk up and the next thing you know someone will be trying to get them to allow ABS or some other radical thing like EFI. Stop that right now

Bill

Yes, lets add all sorts of technology, just like F1. And, maybe, we can have the same kind of screwed up racing they have.

Being a FORMER NASCAR fan and a huge fan of F1, I am curious as to what you think is "screwed up" about F1.

The Frances have turned NASCAR into a boring version of IROC. Everybody is in the same cars with different decals to make them a Ford, Chevy, Dodge or Toyota (who doesn't even make a pushrod engine for the street but has one for NASCAR???). I don't even watch NASCAR anymore, it's a joke.

hobbymanbill - 24 March 2008 06:59 PM

I don't have any facts to support this, it's completely anecdotal, but NASCAR tire troubles are almost always at HIGH banked tracks. I don't ever remember tire problems at the flat ovals, and certainly not at the road courses.

If we just accept that for the moment, the problem occurs PRIMARILY on the right front. All the formulas for down-force and so on MAY indicate that F1 and CUP cars put the same or at least similar loads on the tires. The fact is though that the load on the right front on a cup car isn't duplicated at any F1 track. Even if the peak load is matched, the duration as mentioned earlier in this thread is not. F1 drivers have long complained about NOT being able to keep enough heat in the tires. NASCAR usually has the opposite problem. So you have a tire that is under almost constant high g lateral load and high heat stress. It also contains quit a bit less gas than a F1 tire.
Nascar 12w x 28h x 15 rim
F1 14-15w x 28h x 15 rim
also because they are both radials the larger sidewall of the NASCAR tire has more flex which also builds heat and adds stress to the carcass. I'm not sure, but I believe the wheel of a F1 car is wider than the tread of the tire. Taking all that into account, Goodyear has a much more difficult job then B F Goodrich. AA JMHO

Bill

F1 mandates 13" wheels: FIA Rules Article 12.4.4 Wheel bead diameter must lie between 328 and 332mm.

markconn58 - 11 April 2008 10:40 AM

hobbymanbill - 24 March 2008 06:59 PM

I don't have any facts to support this, it's completely anecdotal, but NASCAR tire troubles are almost always at HIGH banked tracks. I don't ever remember tire problems at the flat ovals, and certainly not at the road courses.

If we just accept that for the moment, the problem occurs PRIMARILY on the right front. All the formulas for down-force and so on MAY indicate that F1 and CUP cars put the same or at least similar loads on the tires. The fact is though that the load on the right front on a cup car isn't duplicated at any F1 track. Even if the peak load is matched, the duration as mentioned earlier in this thread is not. F1 drivers have long complained about NOT being able to keep enough heat in the tires. NASCAR usually has the opposite problem. So you have a tire that is under almost constant high g lateral load and high heat stress. It also contains quit a bit less gas than a F1 tire.
Nascar 12w x 28h x 15 rim
F1 14-15w x 28h x 15 rim
also because they are both radials the larger sidewall of the NASCAR tire has more flex which also builds heat and adds stress to the carcass. I'm not sure, but I believe the wheel of a F1 car is wider than the tread of the tire. Taking all that into account, Goodyear has a much more difficult job then B F Goodrich. AA JMHO

Bill

F1 mandates 13" wheels: FIA Rules Article 12.4.4 Wheel bead diameter must lie between 328 and 332mm.

SORRY, I looked everywhere I could think of for that and couldn't find it. The wheel reference I found was old. The diameter of the rim however isn't as big a deal as the width of the rim. That is what changes the performance of the tire the most. When you mount a tire to a rim that is WIDER then the tread of the tire, you significantly change the tire's ability to deal with side loading. Particularly in a RADIAL TIRE, which both F1 & NASCAR use. If you watch the tire CAM mounted on both cars, the F1 tire virtually doesn't flex under side load. The NASCAR tire however has a CONSIDERABLE roll under to it when it is under side load. The movement of the carcass ADDS HEAT and stress. Thanks for giving me the correct data.

Bill

F1. Very little passing during the race. A lot of position changes occur during pit stops. O.K. maybe there are some passing during the race. But, my luck, it would happen at some other point on the race course, rather than where I am sitting.

NoviVespa3 - 21 March 2008 02:08 AM

Yes, lets add all sorts of technology, just like F1. And, maybe, we can have the same kind of screwed up racing they have.

You mean, as compared to the obese walrus races Nascar puts on? With all the cruising for 400 miles and a 100 mile sprint? Where you can be butt slow, git yerself a coupla 'luckydawgs', and boogity boogity boogity back to the top 5? Greeeeaaaaaaaaaattttttttttttt...........