I am going to have a second set of wheels and tires for the 2013 autocross season. I have to decide if I want to run a street tire to drive to the events or a slick tire and change them at the event.

1. I am running D-stock. Can I run either tire and still be in D-stock, or if I go to a slick will I be put in a different class?

2. How wide of tire can I go on my car without rubbing? Is it better to go up to 225 or even 235 width or will that change the turning characteristics of the car too much? I am running the Stock JCW Sport suspension so the car is a little lower than standard but not much.

Right now I am likely going to get the Dunlop star spec 2 in 215/40/17 but want to get all the information to think about going with a race slick to maximize grip.

My last concern is continuing to learn to drive the car at the limits. 2012 was my first autocross season. Is it better to continue learning with a street tire that has some audible feedback or does that not really matter?

 

I'm planning on sticking with street tires. I don't want the hassle of changing at the event.

 

I'd run the Dunlops another year.

The Hoosier A6 is the alternative. Both are OK in D Stock.

The Hoosier in a 205 has a full 9" of tread width, so no need to go wider if that's your preference.

The Hoosier offers a bit more grip in exchange for a narrower tolerance for slip angle, a greater sensitivity to temperature, and less audible feedback.

On my previous car the Hoosiers would produce a bit more than 1.21 g lateral, and the best ST rubber would top out at about 1.12 g.

And of course since the Mini puts no heat in the back end at all, the 1st run is a slidefest - I used to go out and spin the damned thing on the 1st slalom with some regularity!

Cheers,

Charlie

 

To be 'competitive' in DS you will need to run R-Comps/Slicks. All stock classes allow R-Comps given you keep to the wheels sizes/spacing/offset by the rules. You can run in RTF or STX with your street tires, again given you keep to the allowed wheel sizes.

As far as actual sizes, I've done 235/40/17s Toyo R1Rs without rubbing. Only slightly heavier turn in. Another MCS driver here has managed 245 Toyos.

Each brand varies, R-Comps are even worse. One MCS here has tried 245/40/17 BF Goodrich R1-S and had a little rubbing on the strut tower. I'm going to run 235 R1-S later in 2013 myself.

 

A local club member said to be prepared to break more parts and wear out more bushings if you run a really sticky tire. Is there any truth to that?

 

Oh, whats the minimum load rating that I should be worried about with a new tire, say either the Kuhmo 710 r-comp or the dunlop star specs? It seems most of the 215 / 40 / 17 are all 83W but my stock tires are higher than that.

 

Of course to be 'competitive' in any class takes quite a bit of practice.

In my case, with an average PAX of 22nd last year in the New England Region, I was competitive. That was my best ever, and the result of 9 years of practice and a lot of help from better drivers.

I started out 6 seconds off the pace in 2004 - now I'm finally down to tenths. Most of the novices at an NER event are in the +4-8 second range, and it's rare for a new driver to get within 2 seconds of a seasoned competitor even in their 2nd year of consistent attendance. I was about average I'd say, in my progress through this prolonged apprenticeship.

The difference between R Comps and ST tires on a 60 second course is about 1.5 seconds (course dependent). Hence the ST PAX of .975 which seems the consensus on the adjustment.

Due to my not reading the rulebook before buying the Works package in '04 I spent two years in ASP - and the 2nd year I ran the Hoosier A6. Fortunately no serious ASP car existed at the time, so I and another novice (in a better car - a blown RX7) learned a bit about auto-crossing and had a lot of fun.

From '06 forward I've been running STX trim, and have sampled the best of the TW 140 ranks. Last year the car was running a full STX chassis with an asymmetrical rim/tire setup that put more width out front. Essentially I learned to drive on street tires - because the '05 season on Hoosiers was such a steep learning curve that I could not take advantage.

So after seven years of street tires I am going back to Hoosiers this year, and yes I am grinning. Stickies are great - let's admit it. I hope that this year I can drive them properly and not be a ham-fisted slider as I was back in '05.

But there are two sides to the Hoosier coin in my experience, that's all I'm suggesting.

Cheers,

Charlie

 

In theory I can see this. There is a certain logic that the stickier tires are transmitting more stress to the car. But the stresses of driving your car 12-15,000 miles a year will still be more than what 30-40 autoX runs will do. Of course if you run almost every weekend on national level concrete courses with new R-Comps...then maybe you have something to consider.

Personally I worry more about HPDE/PDX/Track Days being hard on the car than autocrossing.

 

Wheel bearing replacement history:
LF only at 92,000
RF only at 119,100

Brake rotor/pad replacement history:
Rear only at 39,942 (who knew??)
Front only at 59,292
Rear (Pad Only) at 79,505
Front only at 119,170
Rear only at 139,989

That's 12 events and about 100 runs/year and one heck of a lot of backroad driving. No race track (except once with the BMWCCA)....

Remember - stickies are not putting a whole bunch more stress on the car - it's less than 10 percent more than a top ranked street tire.

 

IMHO..... spend your time and money on driving school, going to as many events as possible for seat time.... and go with a good set of street tires like the Star Spec Z2's you mentioned.... you will not be competive in D-stock unless you have Hooisers & the experieince/skill to make use of them (spending $250 a tire to be crushed will quickly become non-fun). The SCCA FWD Street tire class is actually a lot of fun and very competitive..... on $100 street tires that will last several seasons. I ran FWD Street Tire last year after several years of D-stock on street tires (just getting seat time) and really enjoyed it! FYI..... it was humbling and informative on what I needed to work on.... for me and my 2007 S to be 2 seconds behind a really good Pro level driver with a standard mini! Good Luck in 2013.... FYI.... I think I will trade in my worn out Hankooks for a set of the new Dunlops.

 

You have some parts to choose from, here too: http://www.parts4euro.com/DCShop/ind...fd50ae3b941552

 

Does that mean my 07 JCW will be in ASP? I thought it's class was DStock?

 

Several years ago the fJCW Minis were classed differently. DS or if modified STX->DSP is the current classing.

 

The ZII is predicted to be a very quick tire. I would certainly consider than to stay stock. We won't be able to test until later in the season.

 

Alex, when is it going to be available?

 

Send me a set.... would be glad to test and provide feedback!