Most effective way to warm tires!

[speedsense]

Now, thinking about those small burnouts. I recall very clearly that not long ago the F1 drivers seemed to perform what visually seemed like far more aggressive burnouts while weaving on their way to the grid than they do nowadays. I'm talking about the ones they do just as they're back onto the main straight, with what seems like all 4 tyres spinning while the car only rotates around its vertical axis
I have a very clear recollection of Alonso doing that a lot stronger than most other drivers during 05-06, and i guess but i'm not sure that during 07-08 that happened as well but to a slightly lesser degree. However presently, and i think that would include 09, they just never seem to do that anymore, at least not as aggressively.
Is this a result of the fully slick tyres being used nowadays? or, if i'm right in thinking they stopped doing it in 07, something that worked better with the michelins or perhaps something that was possible with the traction control enabled cars? thoughts?

Tire compounds that are widely apart from each other vs compounds only one step apart and how they used tire blankets then vs now, would be some of the reasons.

[marcush.]

747h again you cought me using wrong terminology..
I´m very much aware that it is feasible and useful(at times )to precondition tyres for longevity by heat cycling them in an oven or by really gently scrubbing them .
What i wanted to really state :
If temps was the single factor to bring the tyre into the working window ..why not heat them to this -optimised- temp.As we can see in f1 rthese days ,the harder compounds still need over one lap to come alive on certain chassis and some drivers can cope with this condition better than others.
I´m absolutely sure it is not the temp you want it is the behaviour of the tyre and this is not a function of temp it is the other way round ..the tyre develops a temp because of the work it is doing.

[DaveKillens]

Alonso used to be very aggressive in whipping his car side-to-side before a start or under the safety car. But he seems to have toned it down, maybe because once he did spin and it cost him.

But most of that weaving we see in almost all racing series is more about removing crud from the tires than heating them up. Here's a photo of cars in parc fermee. Yes, the drivers deliberately drove in the marbles to pick up the crud, but it does show that there's a lot of crud on the track.



So a car wouldn't pick up as much under a safety car, but it does pick up quite a lot, and this needs to be removed before the green flag flies. So the driver scrubs it off by hard left and rights.

And there's another driver belief, that if he warms up the rear tires by doing a minor burnout, the car won't posess dangerous oversteer characteristics at the start.

[alelanza]

Tire compounds that are widely apart from each other vs compounds only one step apart and how they used tire blankets then vs now, would be some of the reasons.

Very true, thx for that input

@DaveKillens

Good points as well. Also i'd imagine another purpose of pit stall burnouts pre race is to start laying down rubber to offer better grip during the race.
BTW, and somewhat off topic, are there any regulations preventing teams from adding any substances that would increase grip in the pitbox surface? It's always fun to watch nascar spraying coke in the floor, though they say it's more for the mechanics' benefit than to offer any increased grip for the tyres.

[speedsense]

747h again you cought me using wrong terminology..
I´m very much aware that it is feasible and useful(at times )to precondition tyres for longevity by heat cycling them in an oven or by really gently scrubbing them .
What i wanted to really state :
If temps was the single factor to bring the tyre into the working window ..why not heat them to this -optimised- temp.As we can see in f1 rthese days ,the harder compounds still need over one lap to come alive on certain chassis and some drivers can cope with this condition better than others.
I´m absolutely sure it is not the temp you want it is the behaviour of the tyre and this is not a function of temp it is the other way round ..the tyre develops a temp because of the work it is doing.

The tire has very little grip when cold and will only do it's desirable work when heated to it's target temp.
If you don't hit or go over the target temp window, you either will under perform or over heat the tire. Either way, it's temp that is important for the workable part of the tire to reach it's wanted behavior.

[bigpat]

I believe weaving at low speed just keeps the driver occupied...

Weaving at low speed just slides the carcass and tears it. You need higher speeds to make it work, as the sidewall needs to flex in order to heat the tyre carcass, and the tread surface deforms.

As mentioned above accelerating, rather than wheelspin, and braking are very effective.

The burnouts and snaking the cars do just prior to the start, merely heats the surface of the tread, as this is important for grip off the line. The fact Alonso (or anyone else) don't snake as aggressively has nothing do with a prior spin, but rather that the Pirelli's are EXTREMELY sensitive to excessive tyre slip.

Martin Brundle has mentioned that the tyres "have a long memory", and pay back any abuse taken early in the tyre stint. So going bananas and sliding prior to the start, hurts you later, and the drivers and engineers have been smart enough to figure it out......

[Jersey Tom]

Weaving at low speed just slides the carcass and tears it.

Tears the carcass does it?

[ESPImperium]

Id love to scrap tyre warmers on all tyres. Then lets see how quickly cars can get their tyres up to temp and getting that lap time from them!

It would save the teams approxematly €40,000 on average at any event.

In effect the drivers who are aggressive at the start would have an advantage but the smoother drivers would have a even larger advantage as they could go as many as 7 ot 8 laps longer than the aggressive dudes and also have one less pit stop a race.

You could also change the pit stop procedures as well, making a limit of only 10 guys working on the car at any one time.

Id like to see a change in the pit stop rules to include a 10 person maximum and hub pressure sensors that dont allow a car away without the correct pressure on the hub to stop de-wheeling happeing after a poor pit stop. But thats me going off topic again.

The most effective way for a car to warm its tyres is to get into a high gear and at slow speed scrub the rubber from side to side in a controlled but aggressive manner. 5th gear at 120KPh or less is what is good for the tyres side wall. However for the surface its all about breaking and accelerating in a controlled and aggressive manner as well, breaking heard enough that you dont lock the brakes and accelerating hard enough not to spin the tyres up. However in that last 350m before your grid slit is where the burn outs need to happen, usually 3, for the rears this is crucuial, as this is where you will get a great start from. Unless you drop clutch 1 too hard and cant control clutch 2 well enough, or you have selected a wrong Bite Point Find setting.

[Lycoming]

I'm pretty sure they would scrap tyre warmers if they could; the current ones are very restricted, being only allowed to heat the tread surface. I think the they're still around for safety reasons. Pit mid race onto completely cold tyres, and there will be a huge speed difference at the pit exit and the first few corners. be like doing 50 kph in the fast lane of the autobahn.

[Jersey Tom]

I'm pretty sure they would scrap tyre warmers if they could; the current ones are very restricted, being only allowed to heat the tread surface. I think the they're still around for safety reasons. Pit mid race onto completely cold tyres, and there will be a huge speed difference at the pit exit and the first few corners. be like doing 50 kph in the fast lane of the autobahn.

Works in other race series. Requires tires that aren't junk (or super junk) outside of a narrow temperature band though.

[adam2003]

heated blankets are the most effective way as they dont take life out of the tyres unlike when they do the warm up lap

[Belatti]

After a while working with NA "cross ply" (Argentinian) Formula Renault 1.6 tyres I started helping a team in Formula 4 (Audi 1.6 engine) where the Brazilian "radial" Pirellis are used.

My experience with NA tyres where: The new tyre / fastest qualy lap from the NA tyre is lap 2 and/or 3. Then, for a good driver that managed his best in lap 2/3, the laptime will probably increase 0,1 sec toward lap 4 and 5 and 0,2s till enter a plateau that will last depending mainly on heat cycles.

After a couple of races working with the Pirellis, I was not so surprised to find that in a 15 min. qualy session, every driver did their best laps in their last lap (that was arround lap 9 or 10). Pirellis have harder compound and they need more heat than these light and relatively low downforce cars can give them in a couple of laps.

Rulebook states that F4 drivers must use their "hard" Pirellis for 3 races, in order to keep costs at bay and teach yourgsters to manage their rubber.

The best way I found to heat Pirellis faster and properly (and without wear them too much) was not to do low speed zig-zags that scrape them to add relatively small heat (what every driver does in the outlap) but to do fast laps from the beggining of qualy sessions, but investing the first 2 or 3 laps in zig-zagging at high speeds in straights. After that, in lap 4 you are in the door of the optimum operating temp (that I can only measure with laptimes statistics) and you can take advantage of 3 or 4 more fast laps that your rivals.

[olefud]

Getting heat into tires is important to optimizing the grip. But temperature is often even more important to pressure to the point that pre-warming can be a safety issue. Without pre-warming, cars start on grossly under inflated tires with marginal handling until heat raises the temperature to a workable range. Of course, pressure keeps rising with temperature and can go to over inflation if starting pressures are increased. It can be a bit of a dilemma.

Getting heat into tire either with warmers or exercise is a needed process. Riding the brakes a bit can help a bunch on pressure -not so much with rubber temp.

[raymondu999]

heated blankets are the most effective way as they dont take life out of the tyres unlike when they do the warm up lap

Do they? I'm not a tyre person but to my understanding, any heat energy into the tyre (which JT calls, to memory, "heat history"), including the energy from the warmers - would have some degrading effect on the tyre.

[bigpat]

Weaving at low speed just slides the carcass and tears it.

Tears the carcass does it?

Sorry, tears away at the tread surface......

The F/Renault tyres might also have a stiffer structure (which cross plies do...), and it would seem that a light weight, relatively low downforce car takes a bit longer to warm the carcass of the tyres up.....

Banning tyre warmers would make the cars trickier to drive, but it would be the same for everyone. The drivers will moan, but that's expected. Problem is, you can't stop people putting tyres out in the sun, or for example, an open box with mirrors, or lenses to magnify light and heat onto the tyres. At least as they are, everyone is in the same situation....