Z16 Autocross

Hello All,

I am just about to start my first year autocrossing my 2004 C5Z. I have been doing a lot of research and purchasing over the last 6 months since I got the car. I have a set of Hoosier A6 tires that will be used at the dry events this year and I have an extra set of wheels with some very tired BFG drag radials on them. I would like to get a good set of street tires for that extra set and have them pull double duty as my race wets. Anyone have any recommendations or experience with doing the same thing? They will get very little use on the street maybe 1000 - 2000 miles but i don't want to burn them up in 200 miles. Do i go with a small tire overall for the rain set? The A6's are 295 front and 315 rear. Thanks in advance for you help.

Brandon Z.
23 SS CR-SCCA

VetteDrmr

Unless your rain conditions have puddling water, I'd just stick with your A6s, for 2 reasons: my experience (admittedly not much here in TX) with wet conditions is that my RA-1s, with almost no tread (certainly not enough to evacuate water) still have a lot more grip than I expected.

2nd, wet surfaces are also cool. The A6s will warm up more than probably any other tire out there, which should also play into more grip on a slick surface.

HTH, and have a good one,
Mike

Z16 Autocross

and if there are standing puddles? Its been known to do that here in Chicago.

VetteDrmr

If you've got puddles then I'd just run on whatever street tires you drove to the track with.

Yeah, I know, I know, "so what street tires would those be?" If you're only going to be driving a couple of thousand miles a year some full tread RA-1s/R-888s might work well. They have a tread wear rating of 100, so they're plenty grippy in the dry. If you want to go with a more conservative tire then the old tried and true Kumho MX (220 rating).

HTH, and have a good one,
Mike

waktasz

My experience with the MX is that they are terrible in the rain, and that was on a Subaru.

Jason

If nobody has wets, the newest street tires will win.
If somebody has wets, they will win.

0MrPickles

The Kumho Ecsta SPT used to be Kumho's un-offical race tire until their wets came out. Good tire, handles REALLY well in the rain, and still a good street tire. Not as grippy at the Hoosier wet radials, but better than most street tires. I did fairly well at Solo Nationals in 2007, during the first heat in the rain/wet pavement, compared to the rest of the group. If stock rims sizes...go with 245s up front and 275s in rear (if primary purpose is for rainy AX days)

I wouldn't use the A6s in rain, unless you like to spin and/or get tail happy!

Kubs

I use Goodyear F1 GS-D3 tires for street and rain. Awesome wet performance! Kinda pricey though.

66IISS

Wow, no one has peddled the Kumho XS yet?

We don't have them yet, but will soon. I drove a car with one at our club's driver school on Saturday and was really impressed with the grip of them. I've heard nothing but rave reviews. I don't have data from the rain we recieved later in the day on Sunday, but I will soon...

trackboss

I will be needing a set of streetable tires soon and I'd like to hear about the XS myself. While looking around for tires I discovered that yokohama advan sports are available in the sizes I need and have a 180 treadwear like the XS. Everything suggests they should be one of the stickiest real street tires(must work in the wet is all I ask). If I don't find some toyo RA-1's in the size i need its probably gonna be the yoko's unless I get some really good suggestions on the XS. They both are similarly priced.

JiminVirginia

Toyo RA1s or Nitto NT01s (with tread) will be better than any true street tire. You'll hate it on true street tires.

Bill Dearborn

It depends on how much rain you are getting and how much build up on the course. I use my Firestone WOs in the rain. In deep water they are really great. However, if most of the course is just wet and there are only a few puddles you are probably better off just using the slicks. A treaded tire gets better traction than a slick when the tread can be put to use getting water out from under the tire. If the course is just wet the tread doesn't help and you are losing a lot of surface area so the best option is to raise the tire pressure in the slick to reduce its footprint.

I attended an autocross last year where it was pouring at the outset of the event so I put the Wide Ovals on and waited for my turn. When I got out on the course the rain had let off some and the course was very wet with a few puddles. The tires slipped around a lot. Other people on slicks were doing better so I put on my old set of Kumho 710s that were about to cord and became instantly competitive even though the Kumhos wouldn't hold at all going through the puddles.

Bill

GettReal

I use a set of R-888s on my OEM 17/18 wheels. Sticky enough and a bit of tread to play out the water variables.

They go on anytime when the track is wet. Otherwise its Hoosier time

rustyguns

V710 has incredible wet track test results

slates

I autocrossed my Z06 with Toyo T1Rs in both wet and dry conditions for the last year. They are not such great tires in the dry, but are very good in the wet. Nice street tires, don't seem to wear much, and reasonably priced.

My new street and autocross tires this year are the Kumho XS. I have 295/17 fronts and 315/18 rears. They fit fine on the stock wheels and there is no rubbing at standard ride height.

Last weekend in Milwaukee was not optimal for the XS tires. Temps in the low 40s and rain in the afternoon. The XSs are NOT good cold weather rain tires. The previous day we had our annual school and had temps in the 70s. I managed a few runs, and was impressed with the grip.

This coming weekend is supposed to be warmer, but rain is in the forecast. If it is dry I will report back.

linutux

Why not use A6's and keep one of these in your track kit:


Seriously, how long does it take to cut tires for the rain?

How hard is it to do "right"?

Has anyone done this?

eschantra

Unless they're old and it's cold lol

Timz06

A true rain tire will completely dominate any street tire. I have a set of goodyear intermediate racing wet tires and I was pulling 1.2 lateral g's in the rain.

Tim

Davinss

That may have been true a few years ago, but the newest crop of street tires are much closer to R's. Last year in E stock at the pro solo national championships someone outran the hoosier wets won on Toyo R1R street tires.