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PZ 08-30-2007 09:03 PM

Autocross FAQ
Thought I would throw together some FAQ's on autocrossing the 3. If you have any to add, I will edit my post with the question and answer.

Here is the current SCCA Solo Rule Book

What class does my 3 fall into?

The classes for the Mazda 3i and 3s are:
H Stock
Street Touring S
Street Touring X
F Street Prepared

The classes for the Mazdaspeed 3 are:
D Stock
Street Touring Ultra
D Street Prepared (under the 4 cyl. mechanical induction catchall)

Right now, the only classes that the 3 and MS3 are competitive are in the Stock Classes.

What can I do to my car and remain in Stock?

First, you should always consult the SCCA rulebook for current rules. The Stock Class rules tend to stay consistent, but you should always check if you are thinking of a new mod.

Stock Class basically requires you to run the car the as presented from the factory. The only changes generally allowed are wear items such as tires (any DOT approved tire is allowed, including R Compounds), brake pads (any pad can be used), exhaust can be changed after the last catalytic converter, the air filter can be changed.

While it is not a wear item, the front sway bar can be changed as well.

For wheels, you are allowed to use any wheel that is dimensionally the same (width and diameter) as the wheels that came with your model car. You can change the offset by .25.

Can I use a smaller rim than what came on the vehicle and stay in Stock?

No, you must use the size that came on your model car.

What are R-Compound tires?

Some manufacturers make tires that are specifically designed to be driven on the track. Because many sanctioning bodies require DOT approved tires, the manufacturers design the tires to meet DOT regulations. Some of the tires that fall into this class are the Hoosier A6 an R6, Kumho V710, BFGoodrich G-Force R1, Hankook Z214 (There are more, but these are the top 4 in autocross)

I put a cold air intake in and dropped the suspension. Is this okay for Stock Class?

These mods will put you into the Street Touring classes. Street Touring S (STS) for the regular 3 and Street Touring Ultra (STU) for the Mazdaspeed3.

Okay, what can I do in Street Touring?

First, you should be aware that the Street Touring rules are still new and, as a result, are still changing. What is legal this year may be illegal next year (and visa-versa) If you are going to build a car to the Street Touring Rules you should get a rulebook and stay current with rules changes.

SOME of the things that you can do are:

Suspension mods (lowering, sway bars, struts)

Engine Mods (Cold air intake, emissions legal headers, mounts, accessory pulleys)

Alternate brake pads and rotors (ie slotted or cross drilled) may be used.

Wheels can be any diameter but may only be 7.5 wide.

Tires may have a maximum section width of 225mm. The UTQG Treadwear rating must be 140 or higher. There are some tires that are on the exclusion list, consult the rulebook.

No limited slips allowed.

There is much more that can be done, but that is the gist of it.

Street Touring X adds:

8 Wheels allowed
Maximum tire is 245mm (but the UTQTG rating is the same)
Diffs are allowed.
High Flow cats are allowed.
Alternate Rotors and Calipers are allowed (provided the rotor is the same size or larger than stock.)

Additional changes for STU are:

Maximum tire is 275mm (but the UTQTG rating is the same) on RWD and FWD

What is Street Prepared?

Street Prepared allows more engine work you are allowed to change anything before and after the head. No cats are required.

Any wheel can be used and any DOT approved tire can be used.

The suspension allowances are a bit more free than in Street Touring.

To be competitive in Street Prepared, you should be prepared to trailer the car

gundal 08-30-2007 09:26 PM

Re: Autocross FAQ
Great information... thanks. Vote for sticky.

CosmicBlueMS3 08-31-2007 07:19 PM

Re: Autocross FAQ
thanks for the writeup PZ, hopefully more 3's come out to play

now lets see about that sticky thing.... 8)

cmedrive 08-31-2007 11:47 PM

Re: Autocross FAQ
Thanks for clearing that up. I mainly like to do track events but would like to get in auto-x. It seems like it would really hone some skills. It is really confusing when you start looking into classing your vehicle. I have read web page after web page about it but was still unsure. I may do my first auto-x on Sept 9th if work doesn't get in the way.

PZ 09-01-2007 09:04 AM

Re: Autocross FAQ
Added Street Touring X to the classes the regular 3 falls into.

lincoln 09-01-2007 10:43 AM

Re: Autocross FAQ
I think that I would have to be in street touring with the current mods i have?

Will I have any chance?

What cars would be my greatest competition?

PZ 09-01-2007 12:53 PM

Re: Autocross FAQ
[quote author=Lincoln link=topic=87808.msg1683639#msg1683639 date=1188657811]
I think that I would have to be in street touring with the current mods i have?

Will I have any chance?

What cars would be my greatest competition?


Yes you would be in Street Touring

Typical competition will be other small cars like Civics, 240SX, Scion and the like.

Your chances will depend on your driving. Realistically, if winning STS is your goal, the 3 is the wrong car to have as it carries too much weight compared to the Civics. Regionally, it will depend on who and what shows up.

travicon 09-01-2007 09:41 PM

Re: Autocross FAQ
very good info!!

i think winning STS more depends on driving ability. i have seen all kinds of cars win in the houston region. such as: Lexus IS300, Toyota Celica(most recent gen), Dodge Stealth, Honda Accord, AE86 Corolla, Honda Civic; possibilities all lie with the driver IMO. I have placed 2nd two times and 3rd once against the afore-mentioned, and that was in an auto.

And PZ: wouldnt Lincoln's SU Engine Mount put him in a diff. class? the rule says any mount substitute for STS must have the same amount of metal. I dunno if the SU mount has more or less, but i thought i would throw it out there.

hmm, and never realized the 3 falls into CSP...thats interesting considering thats what my GF's dad drives his Miata in. maybe i could jump in and steal his thunder.

PZ 09-02-2007 09:33 AM

Re: Autocross FAQ
Yes, if the SU mount has more metal it will bump him into CSP.

As far as the competitiveness of the 3 in STS: Yes, a top level driver with be able to compete in a 3 (or any other car) if there are no other top level drivers in better cars.

It all comes down to weight vs tire. Since STS is limited to 225 width tires, a lighter car is preferable. Early 90's civic hatchs weigh about 2200lb. A 2004 3i Sport weighs in at about 2700lb and they just got heavier from there.

It's also a matter of viewpoint. I look at it from a National perspective. Regionally, any car can be competitive if the driver is good, but if I were going to build and STS or X car, the 3 is not where I would start.

As far as Street Prepared, the 3 probably belongs in DSP, but until someone writes a letter asking it to be classified, it will stay in CSP.


travicon 09-03-2007 01:41 AM

Re: Autocross FAQ
Agreed PZ. I think for all intensive purposes that we can assume Lincoln just wants to have fun in his car, which is what will happen at a local event. You are correct in saying that it is a matter of viewpoint. You look at it as competing on a national stage, where-as I look at it as going and having fun and tossing my modded car around a bit, and learning a thing or two also. I just dont want others reading this to be discouraged. A decent driver can take his car to a local SCCA event and be competitive, will he win nationals? No. But speaking from a college-kid wanting some legal fun in my car and some friendly competition standpoint, its the most fun you can have with your car for $30.

Speaking of national competitors, a guy named Andy Hollis was at this past auto-x in his nationals prepped STS Civic blowing everyone else in the class and in the PAX away. Didnt realize those Civics were such a big deal until I grabbed an old SCCA magazine from 2005 at a friends house, and saw that 9 of 11 cars listed were those early gen civics.

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