Auto-x in HS class with a MZ3i sedan... model upgrade questions.

[flatlander937]

So I am new to Mazdas, and new to auto-x as well... I've only attended one event as a spectator and it was a ton of fun! I rode along in a bunch of different cars, had a great time.

I was wondering about some technicality questions when it comes to my car in particular...

As you can see, it's an 09 sedan, 2.0L 3i with the touring package. I have some questions regarding what is within the rules to eventually make this thing competitive(locally) in H-Stock for SCCA auto-x:

-16x6.5" rims are allowed since it is a sedan(I understand the wagons are not allowed 16s since they all had 17s)... is 16x6.5 or 17x6.5 the preferred choice for more competitive MZ3 sedan auto-xers? More curious than anything... I want to pick up a 2nd set of wheels with which to mount some summer tires on for auto-x... and after those wear out jump up to some DOT stickies.

-I noticed that all of the Mazda3s are grouped into the same class(except for the Speed 3s)... so does this mean anything from another MZ3 can be used?

-For instance: Could I install the rotors/pads/calipers from a 2.3l "S" model on my car and remain legal?

-Is pulling the ABS fuse legal? Does anybody find the need to disable ABS for auto-x? Luckily my car has no TCS or DSC... it's basically a bare bones 3i AFAIK... single disc player, no heated seats, etc. Only option it has seems to be the 17" wheels and fog lights... I'm guessing some kind of appearance package?

-What about camber adjustment in the front... the factory does not "technically" allow the installation of camber plates or anything to get more negative camber up front do they? So illegal right?

Thanks for the help in advance!

 

[Gibbsinator]

Only advice I think I can add is that a 16" rim will provide slightly faster speeds with slightly lower grip. The reverse is true for 17" it will provide slightly lower speed and slightly higher grip. This is obviously due to weight of rim and increased size of tire. Of course aftermarket 17" rims that are even lighter than your 16" rim would perhaps be better in both ways.

Props on the model though, we have an '09 3i also, my '04 3i doesn't have ABS though, was an option that year.

 

[WillD]

Between the two sizes you listed (16x6.5 and 17x6.5) the 16x6.5 will be faster and will not provide any less grip. This is assuming that you are using the same section width tires on both wheels in that comparison. Since you are restricted to stock sized wheels, I would go with something in 16 because it will be lighter with the same width. The only good reason I could see for going with the 17's would be for gearing.

I think a good start would be to check out the 2012 SCCA solo rules: http://scca.cdn.racersites.com/prod/assets/2012_Solo_Rules_February_reduced.pdf

I perused the stock category rules (section 13) and didn't see anything that specifically allows the disconnection of ABS (not sure why you would want to anyways) or the use of rotors from a different trim level of the same model )(again, I seriously doubt that is allowed and I'm not sure why you would want to). I know it says what is allowed to suspension and camber pretty specifically.

Since you're in Dayton I assume you'll run with the Cincy region SCCA?
I do a lot of OVR (Columbus) SCCA events, if you ever make it up to any of those let me know. There's usually a good contingent of Mazda folks.

 

[flatlander937]

Only advice I think I can add is that a 16" rim will provide slightly faster speeds with slightly lower grip. The reverse is true for 17" it will provide slightly lower speed and slightly higher grip. This is obviously due to weight of rim and increased size of tire. Of course aftermarket 17" rims that are even lighter than your 16" rim would perhaps be better in both ways.

Props on the model though, we have an '09 3i also, my '04 3i doesn't have ABS though, was an option that year.

I don't know about the 16" being less grip... maybe slightly "squishier" feeling in turns due to a little more sidewall, but based on what all the Miata guys do(run 14" wheels with the biggest tire that can unsafely-for-normal-driving-but-work-great-for-auto-x fit on it.

Between the two sizes you listed (16x6.5 and 17x6.5) the 16x6.5 will be faster and will not provide any less grip. This is assuming that you are using the same section width tires on both wheels in that comparison. Since you are restricted to stock sized wheels, I would go with something in 16 because it will be lighter with the same width. The only good reason I could see for going with the 17's would be for gearing.

I think a good start would be to check out the 2012 SCCA solo rules: http://scca.cdn.racersites.com/prod/assets/2012_Solo_Rules_February_reduced.pdf

I perused the stock category rules (section 13) and didn't see anything that specifically allows the disconnection of ABS (not sure why you would want to anyways) or the use of rotors from a different trim level of the same model )(again, I seriously doubt that is allowed and I'm not sure why you would want to). I know it says what is allowed to suspension and camber pretty specifically.

Since you're in Dayton I assume you'll run with the Cincy region SCCA?
I do a lot of OVR (Columbus) SCCA events, if you ever make it up to any of those let me know. There's usually a good contingent of Mazda folks.

Thanks! I have the rulebook saved on my desktop and have tried skimming it every so often, I read all of section 13 and found this though:

"Option package conversions may be performed between specific vehicles
of a particular make and model, but only between configurations
from within a particular model year. Such conversions must be totally
complete and the resultant car must meet all requirements of this Section.
These requirements are not met by simply pulling a fuse to disable
a feature which distinguishes one model from another."

Translated I think that means I would have to swap in a 2.3l motor and whatever other options that would come with(including traction control/stability control/whatever).

The reason for wanting to switch to bigger brakes is pretty obvious... stop faster. IIRC the 2.3 has rotors about 1" bigger than the 2.0L cars? You can actually see that the backing plate is noticably larger than the rotor is on my car.

Also found this:

"If a modification is not specifically authorized in this or previous sections
of these Rules, it is not allowed."

Pretty simple... if it doesn't say it's allowed, it is not.

"Electronic traction and/or stability control systems may be turned off
or disabled, as long as this does not require connection to an external
system, removal of any part, or the substitution or modification
of any part."

This is pertaining to DSC/TCS, but if ABS falls in the same category that would mean no to pulling fuses.

FWIW I was moreso just asking... I haven't actually gotten the ABS to kick in yet... I took my MZ3 out on some country roads and horsed around a bit... I don't think I'll be needing to worry about the ABS issue. I only asked because I've driven some cars that have REALLY terrible ABS systems that kick in WAY too early.




Yeah I plan on running as many events with the Cincy SCCA as possible this year... will probably take a few month break when the baby arrives/around that time, but otherwise yeah. I found out there is a Western Ohio Region SCCA... but their website is very out of date... makes me wonder if there is anything even going on anymore? http://www.worscca.org/

I will be sure to keep an eye on your region SCCA... the OSU lot is about 1.5 hours away, and the Hebron location is 2 hours away. All the Cincy events are pretty much exactly 1 hour from me... but I will definitely make it a point to make it to an event or two! Do you have any details on the "Driver's school" on 5/12? Sounds like something I might benefit from. Unfortunately it looks like most of the weekends interfere with each other between the two regions, but the "test and tune" on April 22 and the June 2 will be perfect off-weekends for the Cincy region where I could come out and drive. Do you go to most of the events?

 

[WillD]

Looks like you've got things pretty well figured out! (2thumbs)

As far as the brakes go... Bigger isn't always better, and this is particularly true with autocross. This isn't road racing where you are going to be slowing a car from high speeds so bigger brakes really are going to be more of a detriment with the extra unsprung weight. I upgraded the brakes on my Miata from NA6 to NA8 and it was the worst thing I could've done for autocross because it just made it easier to lock up when braking.

But you are right as far as switching everything over so it matches a certain package. The Miata guys do it taking a A or B package car to a base level car with no air conditioning etc.

The WOR region does have events (I've never been) but they will probably be updating their site with dates in the next month or so.

I go to most of the OSU events because I have family in Columbus (I actually live in Cleveland). They have a new lot that is a bit farther from me on the south side of Columbus. The driver's school is just a day when they have 15-20 drivers that want to learn from more experienced guys come out and drive and get a bunch of runs with "instructors" in the car. If you're looking for lots of practice with someone who knows what they are doing it's a good thing to do.

 

[flatlander937]

Looks like you've got things pretty well figured out! (2thumbs)

As far as the brakes go... Bigger isn't always better, and this is particularly true with autocross. This isn't road racing where you are going to be slowing a car from high speeds so bigger brakes really are going to be more of a detriment with the extra unsprung weight. I upgraded the brakes on my Miata from NA6 to NA8 and it was the worst thing I could've done for autocross because it just made it easier to lock up when braking.

But you are right as far as switching everything over so it matches a certain package. The Miata guys do it taking a A or B package car to a base level car with no air conditioning etc.

The WOR region does have events (I've never been) but they will probably be updating their site with dates in the next month or so.

I go to most of the OSU events because I have family in Columbus (I actually live in Cleveland). They have a new lot that is a bit farther from me on the south side of Columbus. The driver's school is just a day when they have 15-20 drivers that want to learn from more experienced guys come out and drive and get a bunch of runs with "instructors" in the car. If you're looking for lots of practice with someone who knows what they are doing it's a good thing to do.

Good to know and thanks for the info!

Ugh... I just found out I'll be in VA Beach the weekend of the driver's school for my sister's wedding (yupnope)

I'll try to remember to send you a PM when I am able to make it to an OVR event!

 

[flatlander937]

Thanks for the help so far... I have a couple more questions...

Motor mounts... I understand the stock ones go out and get sloppy on a regular basis... especially the rear/transmission mount. I'd like to replace it since I get a small amount of wheel hop and mounts are cheap... I take it that no aftermarket mounts are allowed unless it looks and is basically identical to the original...

"Alternate components which are normally expendable and considered
replacement parts (e.g., engine and wheel bearings, seals, gaskets,
filters, belts, bolts, bulbs, batteries, brake rotors, clutch discs, pressure
plates, suspension bushings, drivetrain mounts, fenders, trim pieces,
etc.) may be used provided they are essentially identical to the standard
parts (e.g. have the same type, size, hardness, weight, material etc.),"

So is there any benefit to running the OEM Mazda mounts(little bit more $) vs standard motor mounts from Napa or Carquest/etc? Do the Mazda mounts seem to last longer or anything to that effect?