Grassroots Motorsports
Issue link: http://grassrootsmotorsports.epubxp.com/i/501675
Grassroots Motorsports 128 FEATURE: STREET TIRE TEST Autocross Lap Times tire driver lap 1 lap 2 run 1 lap 1 lap 2 run 2 lap 1 lap 2 run 3 avg. run best run fyer lap BFGoodrich g-Force Rival David 24.841 24.763 49.60 24.566 24.63 49.20 24.564 24.603 49.17 49.3 49.2 24.6 Yokohama Advan AD08R David 24.291 25.039 49.33 24.52 24.52 49.04 25.236 24.81 50.05 49.5 49.0 24.3 Dunlop Direzza ZII Star Spec David 24.393 24.486 48.88 24.055 24.29 48.35 24.039 24.299 48.34 48.5 48.3 24.0 BFGoodrich g-Force Rival (2nd retest) David 24.795 24.913 49.71 24.597 24.563 49.16 24.669 24.74 49.41 49.4 49.2 24.6 Bridgestone RE-71R David 24.508 24.595 49.10 24.015 24.259 48.27 23.816 24.622 48.44 48.6 48.3 23.8 BFGoodrich g-Force Rival-S David 23.659 23.729 47.39 23.621 23.849 47.47 23.942 23.897 47.84 47.6 47.4 23.6 BFGoodrich g-Force Rival (3rd retest) David 25.212 24.966 50.18 24.937 24.708 49.65 25.218 24.677 49.90 49.9 49.6 24.7 BFGoodrich g-Force Rival Andy 25.275 25.337 50.61 25.251 24.84 50.09 25.062 24.976 50.04 50.2 50.0 24.8 Yokohama Advan AD08R Andy 25.236 24.81 50.05 25.045 24.668 49.71 25.141 25.158 50.30 50.0 49.7 24.7 Dunlop Direzza ZII Star Spec Andy 24.84 24.873 49.71 24.732 24.811 49.54 24.866 24.456 49.32 49.5 49.3 24.5 BFGoodrich g-Force Rival (2nd retest) Andy 25.464 25.488 50.95 25.338 25.11 50.45 25.243 25.1 50.34 50.6 50.3 25.1 Bridgestone RE-71R Andy 24.527 24.496 49.02 24.256 24.013 48.27 24.575 24.283 48.86 48.7 48.3 24.0 BFGoodrich g-Force Rival-S Andy 24.362 24.29 48.65 24.275 24.352 48.63 24.217 24.172 48.39 48.6 48.4 24.2 BFGoodrich g-Force Rival (3rd retest) Andy 25.092 24.834 49.93 24.918 24.91 49.83 25.069 24.927 50.00 49.9 49.8 24.8 Skidpad Data tire pressure lap 1 lap 2 lap 3 total BFGoodrich g-Force Rival 32 psi 9.934 9.997 9.982 9.971 Dunlop Direzza ZII Star Spec 32 psi 9.756 9.768 9.763 9.762 Yokohama Advan AD08R 36 psi 9.672 9.651 9.832 9.718 Bridgestone RE-71R 28 psi 9.645 9.715 9.708 9.689 BFGoodrich g-Force Rival-S 28 psi 9.618 9.568 9.619 9.602 (all times in seconds) Who Won the War? In many ways, the test was a stale- mate. For sure the class of 2015 domi- nated, but each member did so in dif- ferent ways. And those differences are what will eventually determine which one is right for you. The tires will also require different setups to extract maxi- mum performance, some of which may be restricted by the rules in your area of the sport. As we often say, testing on your own car is the only way to know for sure. But you should now be armed with enough info to make an educated guess on where to start. People who are used to Dunlop ZII tires–and have cars set up for those tires– will likely prefer the Bridgestone RE-71R. Those who come from the looser Toyo Proxes R1R and Hankook RS3 camps will likely gravitate toward the Rival-S. The Rival-S undoubtedly showed the most potential, topping the time sheets for both of our drivers. We'll continue to reevalu- ate both front-runners throughout the year. Next up is track testing. Can the Rival-S stand up to time trials? How about the RE-71R? What about longer enduro competitions? Wet weather? Rim size and camber dependencies? All this and more as the testing season continues here at GRM. Stay tuned.