Thank you Jim, will the Kosei K4R enable me to stay in DS ? Will the Wheels be strong enough that if i decide to use them and the RE11 as my street tires as well as the tires for autos? Do you run with the RE11 as a daily driver?

 

Yes, the wheels are legal for a MCS in DS. In fact, they're also legal for the MC non-S in HS, which is what I had looked at those wheels for. I would use those wheels on the road too. I trust that Tire Rack wouldn't sell them if they weren't strong enough.

The RE-11's also work fine on the road. I use them for regular driving on a Cayman S, as well as for most autocrosses. My guess is that the RE-11's are somewhat better, and longer lasting, for regular driving than the Dunlop Star Specs, which are also very popular for AX and cost less.

 

For choice of wheels- stock 16" vs Kosei K4R

Both are fine and legal for stock classes, cost is usually more for less weight which is always a plus as it helps in braking and acceleration. Kosei makes a gravity cast alloy wheel which reduces the cost and is reasonably strong on a budget. Forged wheels are stronger and can be lighter but cost much more. Any wheel that is lighter can be damaged so always be careful, autocrossing is relatively easy on wheels.

Autocross alignment is more aggressive for quick steering but the settings I mentioned are somewhat toned down so that if you did use them it would not be difficult to do street driving due to the toe settings. Tire wear would be slightly affected by the toe out setting but it is small.

I have driven on the street with front toe out 1/8" and tire wear and handling were fine as far as I could tell. 1/16" toe out or if you want zero toe is fine and more responsive than the stock toe in setting. Rear toe should be slightly toe in for stability in a straight line.

Front camber is helpful when maxed out as this helps use more of the front tires in cornering, rear camber should be minimized to reduce understeer which is common in Front wheel drive cars.

Any Extreme Summer tire can be used for daily driving but they will wear out faster than most other tires. If you have a low mileage commute or only drive a little then any tire will work fine, for longer commutes the daily driver tire should be an all season one in a slightly more narrow/ slightly taller sidewall size.

So when I want to drive at a track or autocross I would put on 17x7 wheels and 205/45-17 Extreme Summer tires, when back on the street then stock 15x5.5 wheels and 195/60-15 UHP All Season tires for better MPG and comfort. I have also driven the Extreme Summer tires on my MINI for 10-12K miles and wear was fine but they are much more rough riding on my roads.

 

Ok, I have just ordered from TireRack Kosei K4R and RE11 205-45-16, this will be my autox set up. What PSI should i use on street use, for the day or so before the event, the event and day or so after event till i can switch back to my RunFlats 17 inch.
What should i run the event at in PSI?

 

Tire pressure is the same for all MINIs no matter which tire- check the driver side door jam.

You can run a little higher than stock like 37 psi cold front and rear for street use.

You can run a little higher on the day of the autocross, try maybe 40 psi front and rear then adjust. You can chalk the shoulders of the tires and see how much of the shoulder you are using. As you use more tire the chalk will be rubbed off. If tire pressure is too high you will not rub off the chalk.

If you don't know how to mark the tire treads then ask someone for help. The best way to adjust tire pressure is to check the tire temperatures with a probe style tire pyrometer. If you check the inner, middle and outer treadblocks right after a run when the tire is still hot you are looking for the middle tread to match either the inner or outer tread reading. It's difficult to use a tire so well to make all three temperatures the same on tire.

If you take a corner fast you will heat up the outer tread, if you accelerate or brake you will heat the tread where the tire is rubbing the track surface.
If your alignment is aggressive you will heat up the inner tread more, stock alignment is not aggressive. Likely your outer tread will be hotest.

It is possible for your tire pressure to be different on the right side vs left or front vs rear, each tire is under a different load given the course and how you drive. Maybe there are more high speed left turns or maybe more right turns- then tire temperatures and pressures (pressure goes up with heat) will be asymmetric.

 

Hi Guys you all are great, thank you . Ok, my Kosei 16s and RE 11 will be in tommorow My second autox is on the 30th
What air pressure should i use for street use ?
what air pressure should i use for autox use ?
thanks

 

How did the autocross go with the new tires. I have an 07 mcs as well and was looking into getting those wheels. How do you like them?