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  • sachilles

    June 4, 2010 12:46 p.m. sachilles HalfDork

    Just curious on opinions.

    For situations like autocross, where you don't have a ton of time to warm up the tires. Is a road race compound like a hoosier R6 better suited to an autocross in comparison to the newest generation of tires built for the street tire classes(dunlop star spec, Bridge RE11/REO1r etc). This also applies to hill climbs where the max run time is around 2-3 minutes, with long waits in between runs.

    Reason for asking is you are more likely to see used take off's in the road racing compounds, where the autox compounds tend to get used until they die. Could make a decent tire test for a future article.

  • oldsaw

    June 4, 2010 1:06 p.m. oldsaw Dork

    All tires need some heat to reach optimal performance. Generally, the softer the compound, the quicker the tire reaches the "best temperature" for adhesion.

    Dedicated DOT autocross tires (like a Hoosier A-series) are softer than the (basically) same tire with the R (race) compound. Both are a lot softer than any street tire and both are inherently faster by a demonstrable measure - usually in seconds.

  • June 4, 2010 1:16 p.m. Soma007 New Reader

    For hill climbs with 2-3min runs I'd definately stick with a real "race" tire. That should be enough time to get an R6 up to temp.

    For autocross its a tougher call, if its sub 60degree's then I'd run the street tires. If its warm, or if you have a codriver then I'd run the R6's again.

  • Cone_Junky

    June 4, 2010 1:34 p.m. Cone_Junky Reader

    I used some old road race R compounds for auto-x for a while. First couple of runs were a little loose, but they still seem to stick better than my street tires.

    Cold or not, slicks still put more rubber to the ground.

  • sachilles

    June 4, 2010 1:54 p.m. sachilles HalfDork

    Thanks for the responses thus far.

    Keep in mind, relative to hill climbs. A loss of traction unexpectedly means an encounter with a tree or rock, not a cone.

    So as I wait for them to warm up....am I going to soil my britches for half the hill? or will I have some sort of progressive notice of the tires grip(in general, I understand all tires are different).

    I can live with gradual grip. On/off type of grip is a little less fun.

    The upside is it's a relatively heavy car for the tire size, so that should generate heat quicker.

    Again I understand there are a LOT of variables here. Thanks everyone.

  • YaNi

    June 4, 2010 2:00 p.m. YaNi Reader

    Are tire warmers legal for hill climbs?

  • sachilles

    June 4, 2010 2:15 p.m. sachilles HalfDork

    I'm not sure on the warmers, but for some reason i think they are not allowed. I will look into that.

  • June 4, 2010 2:42 p.m. Don49 New Reader

    Road race tires will be very predictable. As they warm up you will feel the grip come in. Even dead cold they will outperform almost all street tires.

 
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