I am new to autocross and have only done a few autocrosses so far (all with NCCBMWCCA). I am running in the Showroom B class and I am thinking about getting a different set of rim and tire since I am currently using all season tire on type 68 rim (I have 2001 330Ci). The tire didn't hold up too well, it's chunking badly (if that's the right word). If I get an aftermarket rim in 17X8 will I get kicked out of Showroom class? (I am thinking about either getting this http://www.edgeracing.com/wheel/20 or a set of used 17X8 all around from 325Ci sport package). This is an excerpt of the rule "Wheels may be replaced but they must be in a size available as a factory-installed option on the car." I believe the factory-installed option on E46 was 17X8 all around or staggered 17X7.5 and 17X8.5.

I am just a beginner and I know that this may not be a big deal for some of you who are more experienced but I just want to make sure that I can still run in the showroom class before I buy new rim and tire since my car is totally stock and I am only planning to run on NCCBMWCCA events. Thanks in advance guys.

I'd say you're fine, that and the fact that they are relatively lax, so unless you're really dominating the class due to an unfair advantage, you're probably safe. That being said, if 17x8 were an option, then of course you'd be alright.

I am new to autocross and have only done a few autocrosses so far (all with NCCBMWCCA). I am running in the Showroom B class and I am thinking about getting a different set of rim and tire since I am currently using all season tire on type 68 rim (I have 2001 330Ci). The tire didn't hold up too well, it's chunking badly (if that's the right word). If I get an aftermarket rim in 17X8 will I get kicked out of Showroom class? (I am thinking about either getting this http://www.edgeracing.com/wheel/20 or a set of used 17X8 all around from 325Ci sport package). This is an excerpt of the rule "Wheels may be replaced but they must be in a size available as a factory-installed option on the car." I believe the factory-installed option on E46 was 17X8 all around or staggered 17X7.5 and 17X8.5.

I am just a beginner and I know that this may not be a big deal for some of you who are more experienced but I just want to make sure that I can still run in the showroom class before I buy new rim and tire since my car is totally stock and I am only planning to run on NCCBMWCCA events. Thanks in advance guys.
I'm almost positive that would be fine. What tires were you looking to get?

The 330 was not available with 17x8 wheels. The factory sport package came with 17x7.5 F and 17x8.5 R....this is your only other legal option.

Keep in mind that tire size needs to be OE as well, meaning you'd need to run the staggered sizes that came on the sport pkg. wheels (IIRC that means 225 F and 255 R.)

If you're not kicking ass, then you're out to have fun. Do what you want and don't worry about classing and just move to the class where your car falls. Have fun, learn to drive faster, then worry about being competitive.

If you're not kicking ass, then you're out to have fun. Do what you want and don't worry about classing and just move to the class where your car falls. Have fun, learn to drive faster, then worry about being competitive.

I am pretty sure I won't kick ass for the foreseeable future :D, I am just out to have fun. I just want to make sure that I won't break any rules before I go out and buy new rim and tire.

I guess based on what Bren said I will have to use my current rim (Type 68) and just buy stickier tire. As far as tire size, if I run staggered rim, can I use same size tire all around? The reason is because 225 tire is cheaper than 245 tire:(. Supposedly it's better to run same size tire all around but I am not sure if it will make any difference at my level (beginner level that is:buttrock).

Btw, I am thinking about either getting Falken Azenis, Bridgestone RE01R, Hankook RS212 or Kumho Ecsta MX (in that order). According to GRM tire test, Azenis is the best autocross tire but not the best street tire and the Bridgestone RE01R is the best compromise for autocross, street and track tire. So I am still not sure which one to get:confused.

Don't worry about the classing, just have fun and learn.

I would run 235s all around. I really like the Ecsta MX, but if I were to do it again, I would go with either the RE-01R or the Azenis. It really boils down to whether you want to head on to a real track, or drive in the rain. The Azenis heat up very quickly on-track, and grease a bit, from everything I've read (take this with a grain of salt, no personal experience). The RE-01Rs are excellent in rain and on-track, but don't offer as much overall grip as the Azenis on a dry autocross course.

I am pretty sure I won't kick ass for the foreseeable future :D, I am just out to have fun. I just want to make sure that I won't break any rules before I go out and buy new rim and tire.

I guess based on what Bren said I will have to use my current rim (Type 68) and just buy stickier tire. As far as tire size, if I run staggered rim, can I use same size tire all around? The reason is because 225 tire is cheaper than 245 tire:(. Supposedly it's better to run same size tire all around but I am not sure if it will make any difference at my level (beginner level that is:buttrock).

Btw, I am thinking about either getting Falken Azenis, Bridgestone RE01R, Hankook RS212 or Kumho Ecsta MX (in that order). According to GRM tire test, Azenis is the best autocross tire but not the best street tire and the Bridgestone RE01R is the best compromise for autocross, street and track tire. So I am still not sure which one to get:confused.


It is within the rules to run a non staggered setup if you want. You can run the 7.5 all the way around. This will allow you to get the tires you want.

To clarify, you can run any wheel and tire as long as it was the same size that was available to your car (either as standard or optional).


Pete

As far as tire size, if I run staggered rim, can I use same size tire all around?
No.

Re-read my post and Pete's.

You could do as Doby suggests and simply run the car in whatever class it fits (after whatever mods you do) and work on your driving, which is the most important aspect anyway.

Btw, I am thinking about either getting Falken Azenis, Bridgestone RE01R, Hankook RS212 or Kumho Ecsta MX (in that order). According to GRM tire test, Azenis is the best autocross tire but not the best street tire and the Bridgestone RE01R is the best compromise for autocross, street and track tire. So I am still not sure which one to get:confused.

I've run the RE01R at the last two NCC events and really like them. (I haven't been able be beat Josh Turner's 335i with Kumho 710s though). I can only say the Bridgestones are better than the 3 or 4 year old shaved MXs that came on the extra set of wheels I bought. Bridgestone has a $100 rebate program right now on a set of four.

I'd recommend the Hankook RS2 Z212. They're cheap, very streetable, and very sticky.

I have a set of the Hankooks and a set of the Falkens that I use in Prepared Touring and SCCA STS. The Falkens are LOUD on the interstate for everyday driving and less stable in the rain than the Hankooks. Initially, the Hankooks had tons of grip for autox and though faded a bit still have a ton of grip left. I just got the Falkens used (and nicely scrubbed), so it's a little early for comment after just one autox and ~300 street miles. The Falkens seemed much quicker during cornering with a stiffer sidewall and more stable while autoxing.