mikew968

Sorry if this repetitive but...On the warm-up lap for a race or qualifing everbody is weaving to warm tires. Does this warm the tires or just clean off rubber. This comes up as there have been issues and near misses on the first lap of qualifiing when guys are trying to get up to temperature.

Thanks, Mike

Greg Fishman

In PCA no one should be scrubbing tires on the outlap since the track is green! Driving hard but less than 100% (slightly earlier braking, less cornering speed) will get the tires up to temp quicker than scrubbing back and forth on the straight away. On the outlap of a race I try to hold back a few hundred feet from the pack and get some speed through a corner or two to clean and warm the tires somewhat.

mikew968

Thanks Greg The issue has been at NASA with weaving tires on the first lap of practice (green track) and the first lap on qualifiing.

Mike

Eric in Chicago

Couple of swerves to clean the tires of junk. I like to take the tight inside line on all the turns of the warm up lap to build up some heat in the tires and like Greg, hang back to get some high speed stops to get heat into the tires and brakes. I think weaving does nothing to really warm up tires. Now if you have fresh Hoosiers, I found the sealing compound to be pretty slick and tossing the car back and forth a few times will get rid of it pretty quickly. At MO this year, I was getting F1 style sides when weaving side to side with fresh R6's until the new compound was gone.
Hey Greg, when are you going to buy a 44 and come out and play??

Greg Fishman

If guys are weaving on the first lap of qualifying under green flag conditions it needs to be addressed by the stewards.

Eric, I hope one day soon I can get another race car. In the meantime, I have a helmet/driver suit and will travel.

Eric in Chicago

Too bad NASA does not have enduros Greg! If I ever get back to PCA (SP3 class now) you'll always have a seat in my car!!
Doing 20.2 at Putman this year trying to keep Mike W. (first poster in this thread) behind me!

Greg Fishman

Eric,
Mike F. said you dumped a lot of weight and it transormed the car. Let me know if you ever need some help crewing for a race. Mid Ohio or Putnam isn't that far from me.

Veloce Raptor

With pretty much all R-comp & race rubber (Hoosiers, shaved Toyos, slicks, etc), the back & forth motion only really cleans off the tire surface. The better way to put heat into the tires (front & rear) is by repeatedly accelerating and then using the brakes (which also warms the brakes).

RedlineMan

Hey;

The answer to the original question is, Yes. It both scrubs the tire surface clean, and flexs the tire casing to build some heat. I'm sure the former is much more successful than the latter, however. Whatever heat you can generate is a bonus, but it is pretty hard to seriously work the tire at slow speeds, and for such a short duration.

kurt M

Bingo. I read and then kept a study on this but cannot find it... In a nutshell same time spent agressive weaving produced about 10% or 20% as much heat as agressive gas/brake cycles. Slight change in #s for high power cars to low power cars but not too much. Sometimes weaving is all you can do if there is not room in front and behind you. Weaving on a mid race track just might put you in the junk rather than scrub it off too.

Mike Buck

I only weave for the first 1/4 mile or so of track after pitout and only if the track is a standing yellow and there is reasonable spacing between me and other cars. Cleans any crap off the tires I might pick up driving from paddock to grid. Not a means for getting heat in the tires. For that I do what Eric said above (i.e. tight line in corners, power out, braking)

Weaving under green conditions should be grounds for a year long ban, IMHO. That is flat dangerous.

Bull

I used to find that under yellow, particularly with a slow pace car, that a combination of weaving and tight corner lines/power/braking cleaned the tires, built some heat in brakes and tires... and helped releave tension on the pace lap!

Larry Herman

I don't know how much it really helps with street/R compound tires once you have warmed things up for the first time. Maybe as everyone is saying just to scrape off the klag. The wheels & tires retain some residual heat, and the pressure usually only falls a few lbs between sessions. It could be of more benefit when it is cold out. Race tires are another story. When you are starting out with 20~22 lbs of air (cold) you do need to warm them to bring the pressures up so that you don't roll the tires off the rims charging into the first corner.

fatbillybob

It seems that cold temps to hot temps are in the range of 6-9 lbs differences for most of the racers I talk to. What can we reasonably expect as far as pressure increase on the first warmup lap rolling to a green flag? I still do not know know how hard I can push my car in the first corner. Quite frankly, others don't seem to care and just go for it. Amazingly, we all don't seem to go flying off the track. Certainly we are not at full race speed but we are not ***** footing it either.

jrotsaert

If people dot it, it helps them very little. The way to heat up is a rear is to accelerate hard a few times. for the fronts, just over turn the wheel very aggressively in slow speed corners until you feel the front end sliding and keep it sliding with the throttle. Do that 4 or 5 times and you'll get real heat in the tires. Once will just clean the tire surface. I usually do that and then for most of my lap I left foot drag the brakes (pretty hard actually) and hardly ever get off the loud pedal. This has worked for me... not trying to give any lessons to anyone.
Incidentally, I did have an off during a warm up lap at DOnnington this year - very embarassing!
JM