My first autocross of the season in the great Pacific Northwest and rain is predicted with temps in the 40's Do I go with my summer Kuhmo Ecsta XS (which I LOVE when it is dry) or do I keep my General All Seasons on for this one?
Can you take both? I can fit my extra wheels/tires in the back. I just get some Les Schwab plastic bags to put them in. If not, I would suggest going with the summer tires and use it as a test day.
Despite the fact that Kumhos are notably bad in the rain, if they have more than 5/32" tread I'd run those. 2/32 is perfect for a track day, 4/32's pushing it in the rain, and 8/32-10/32 is brand new. While the all seasons may have a more open tread pattern, the rubber mix they use is less sticky overall but more sticky in subzero temperatures. My favorite tires in the rain are full tread Dunlop Star Specs. I've done a couple track weekends in the rain on those tires and it's amazing how much more grip they have than other tires. Bridgestone RE-11's are also great - it's a combination of just enough tread and coming up to heat quickly.
Technique is just as important in the rain as the tires are. Of course tread is important. I've got 2 FTD's in all my years of autocrossing and both were in the rain. First off, I'd add about 5 pounds to the tires all around. That gets a bit less tire on the pavement and decreases the chances of hydroplaning. Don't worry about horsepower. Rain is a big equalizer. ya still have decent braking, just don't lock 'em up. Cornering isn't as good as it is in the dry either. Surprise huh? Make the course a bunch of little drag strips. Power on easy, brake a bit earlier and easier, roll through the corners, then back on the power. Smooth is always important in an autocross but in the rain even more so. Let us know how ya do!
Are you going to be at the Icebreaker tomorrow? If so, we'll see you there, and it's only a 30%chance of rain in the afternoon. :beer
Well, the Practice Day and first Autocross of the season are behind me. As always... I am humbled by the skills of my competitors and by all that I have to learn. I ran with the Kuhmo's both days (6/32 front, 5/32 rear). Day 1 was about 40 degrees and light rain with wet pavement and puddles. It was very slick, almost like grease on the tires. I did my best to limit throttle input and take it easy around the corners. I did get a couple of better clean runs in. Day 2 was 37 degrees and a very light mist/fog. The pavement was damp and most puddles were gone. The tires (and I) did quite a bit better. Much more traction around the corners. Slow in, fast out... slow in, fast out..... I can compare myself and setup with a very good and consistent MINI driver as well as with the field. On Day 1 my PAX times put me in the 23rd %tile, Day 2 I was in the 49th%tile. That is quite a difference. I'd like to think I got that much better and on that trajectory I'll be taking top PAX honors in about 5 events. I am guessing that in relative terms, the Kuhmos are better as it get drier. Also, on Day 1 the other MINI driver was in all-season's and the closest I could get to his time was 2.8 seconds. On Day 2 he switched to his Kuhmo's and I got within .9 secs. I finished 6th out of 10 in the Street Tire class. I felt good about how I drove. Still have lots to learn. Season 2 has begun and I can hardly wait for the next event. FUN FUN FUN Thanks for everyone's input. Chime in if you have an opinion but as of now, I'll be bringing the all-seasons in truly wet weather.
Bringing an old thread back up just to add another possible rain day tire to the mix. I ran last year with a set of Toyo Proxes R1Rs that are very good in the dry with the right tire pressures. Turns out, they're great in the wet too! I accidentally over inflated them for this day and was running 43 psi where normally I'd be running 34-38. My dyslexia strikes again! But with good results this time. I ended up fighting for FTD from a field 60 or so cars which included S4's, STI's and other 4WD cars as well as some great drivers! In the end, a very well set up and driven Miata beat me by just .01 of a sec.
See my post above, the extra air gets some of the rubber off the pavement. Sounds like you've done pretty well there.