Travisivart190

iTrader: (1)

Just looking to start up a general autocross thread, where if anyone has questions regarding the new rule set, they can ask here. Have there been any rule changes that promote Miata's to be dominant where they previously were not? What are the classes someone should try to conform to, if they are building what I hope will eventually be a regionally competing car? I've searched around, and it looks like XP, and SSM are a couple choices?
Thanks for the help guys.
Travis

Doppelgänger

iTrader: (12)

Building a Miata to be SSM or XP competitive is a pretty large task...at least on a national level. I have not seen the '10 rules myself yet, just seen the new PAX numbers (not happy).

Travisivart190

iTrader: (1)

That's what I've noticed personally. Are there any other classes that welcome a more streetable car? It seems to me that in order to be competitive in SSM, you are going to be building a 40k$ car which would be pretty hard to drive on the street. It looks like in order to compete with some of the FD's, which are dominant in my region, I'll need much more power than I can do on my measly income. We won't even go into XP, because it's doubly so.

Doppelgänger

iTrader: (12)

Oh trust me, I once competed in an event with the presence of Strelniek/McClure and Dan Chadwick...it was a humbling day to say the least lol. Honestly, 300rwhp should be enough, it's matching the grip that's the tought part. They run 315's all the way around...so running the 275 Hoosiers and a good suspension is where it's at. ...and a good diff.

Travisivart190

iTrader: (1)

Hm, that's going to be exceptionally pricey. A6's alone are going to cost me 1k$, and probably will not last a whole season of SCCA, and club events. I need to get my gearing figured out. My gearing is exceptionally short. I'm not sure what I'm running in the rear with the Torsen, 5sp. combo. I know I should keep the 5sp for length, but what's preferable for the autox guys?
On the plus side I am upgrading my brakes soon enough to the Track Speed Wilwood's. Should shed some weight and keep my car stopping on point

Doppelgänger

iTrader: (12)

Yeah, that's why I'm running V710s. Being the ricer I am, I run the 215-40/17 flavor because I am running gigantor Brembo brakes. I'd like to see Kumho get more competitive with their available sizes for the V710. If I wanted to go all-the-****-out, I would cut my fenders, install flares and run 17x9/17x10 wheels with 315-35/17

What year is your car/your diff? I honestly don't think there is a "perfect" gear ratio for autoX. I'm running a 6-spd/3.9 Torsen and on some tracks the gearing is perfect..other times it sucks and I cannot imagine anything that would fit in the middle. Most of the time I used 2nd gear with no problems, but there are some configurations where I jump into 3rd. My problems is I have enough available grip that I can make the Torsen go into open-diff-mode.

Travisivart190

iTrader: (1)

The car is a 1991, the diff I believe is a 1994, but don't quote me. I bought it with the car. Thinking about it, out here more often than not we're on some smaller courses. The only place I know for sure I'll have to shift into third is Monster Park...Everywhere else I may be okay.

Chris Swearingen

iTrader: (1)

A couple of minor rule changes for 2010 should help miatas out. Of course they can help most of the other cars in the class as well.

1) replacement of pop up headlights with fixed
2) removal of passenger side airbag without backdating the dash
3) front canards = 15% of wing allowance


The 275s are pretty much the max tire you can run in SSM because you can't modify anything inside the hub face, so to go wider you would have to you out which makes the car wider as well.

Gearing is somewhat course and power dependent. My current 7600 rpm revlimit and 5 speed with 3.909 gears on the 275s puts me at just a fraction over 69 mph in second. The 3.63s would put me just over 74 mph. I ran out of second at Nationals this year, so I am most likely going to jump up to the 3.63s and count on my torque curve to see me through on those courses that aren't quite that fast.

kotomile

iTrader: (24)

OP, are you going to participate in Solo 1 or Autocross?

webby459

iTrader: (8)

The best autocross classes for Miatas are STS and ES, period. Especially if you want to maintain street-ability. That said, I am going at it next year with my turbo SSM car. I'll be doing Divs, a Tour or two, and if all goes well Nationals at season's end.

My car is only half-prepped, and already very expensive. I haven't even started adding lightness. 40k is a great estimate for a reasonably competitive build, without considering the overall effectiveness of the Miata in the class. The Miata may be a decent car for the class, but as Chris S said, you need to address the tires right away on your build, and work from there.

Travisivart190

iTrader: (1)

Yeah, I need to stop stressing over the small things, and get out there and see how my gearing fares. That and get myself some down force eventually.

DURRR. Solo 2, sorry. I'm a retard.

I've spent thousands on this car, and I just feel discouraged that I haven't even skimmed what it takes to be competitive, at least in the SCCA realm. I think I may end up not competing as much this season, and just do club events. Luckily the UFO guys run quite a bit, and I can get twice as many runs, for $15 dollars more. They also cater lunch.

Thanks guys, let's keep this thread going, it's helped me a lot. Maybe it'll get some autocross converts to start showing up

kotomile

iTrader: (24)

As you know already, the Marina site is kinda slick. I hate running on concrete. But you know what the surface is now so you can plan your suspension based off of that. Also check out the American Autocross (IIRC that's the name) guys. They run faster courses, I was a lot more competitive with them.

When did that start?

Travisivart190

iTrader: (1)

I haven't done any American Autocross events. IIRC didn't they used to run out of Atwater a bunch, before it was unfortunately closed down?

I might be smoking more rocks than my body can handle, it was Golden Gate Lotus Club that actually catered lunch. That was a fun event. I drove my Dad's pig understeering stock automatic 530i. Not UFO. I don't believe I have done an event with them.

kotomile

iTrader: (24)

Dunno about that, I ran with them at Marina. Fun courses.

miatamania

iTrader: (9)

With that much power at national tours, the A6s will only be at their prime for maybe an event or two if you are planning on winning. Now the good thing is if you can build it to be somewhat competitive in a NASA TT class you can win free tires. (which is what I am doing with the CSP car, allowing it to remain in a decent TT class for NASA TT)

CSP is even getting tough for early cars now. Though with enough power and a motor built within SP specs you can still make an NA do pretty well.



Creating a nationally competitive miata is rough. It comes down to a LOT of money in SSM. No idea about XP, that class is insane.

flier129

iTrader: (7)

Damn, $40k to be competitive? I would figure around $25k for an n/a.

I just wonder how miatas will do in the c stock this year. str looks interesting as well.

Travisivart190

iTrader: (1)

Last time I ran with them, and the time before they had lunch catered for us. Anyhow, it's always nice going out on a course designed for smaller cars. The courses are always a blast to drive, and surprisingly the lotus community is really friendly. A lot of those guys came from Miata's.

Explain more about the Nasa TT classes? I've never heard of this.

There's a really fantastic thread about building the SSM Miata, which I am currently not able to find. But in any case, they figured it would cost about 40k$ from buying the car, to completion in order to make something that could actually compete. XP even more so.

Doppelgänger

iTrader: (12)

Oddly enough, I didn't "build" my car for SSM. It just happens to fit in there and be competitive in local SSM. I know I wouldn't be in the top 5 at nat'l events, but I'd still go for the time and to get to know people out there. It's about having fun too. Go to a bunch of your local events, be consistant, get to know the big guns...and maybe look into co-driving with one of the front runners.

mikewolf

iTrader: (2)

I would have to disagree with you and say that CSP is a much better miata class than STS. Miata's win CSP nationally, they tend to get beat by crx's in STS.

If you want to be competitive in SSM or XP without spending $40k, just buy the FD that came 2nd at nationals. It was forsale last week on scca forums for under $20k.

Chris Swearingen

iTrader: (1)

Is this the one you were thinking of? It's getting a little dated. Some rule changes have helped, but the basic foundation is still pretty strong.

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