Cal Club Autocross Forums

And I've started to look toward the NC, but I wasn't really sure what to look for. Should I go for the 1.8l or the 2.0l? 5spd or 6spd? 2006 or 2007? What kind of issues should expect to see while I'm out on course with it? These are the kind of questions that have been keeping me up at night and I was hoping to get some feedback from current Miata owners.

What class would you be aiming for? I'm not an expert on NCs, and I forget which year the redline changed, but I think the 5 speed is the transmission you want in the early ones. Later ones, I'm not sure it matters so much (if there is still the option). Also, some early ones come with 16x6.5" wheels, which leave you with the choice of either with bad 16" tire sizes, or hard to find 17x6.5" wheels. The facelifted ones are more competitive, but I'm not sure about the details.

Max Guijarro wrote:And I've started to look toward the NC, but I wasn't really sure what to look for. Should I go for the 1.8l or the 2.0l? 5spd or 6spd? 2006 or 2007? What kind of issues should expect to see while I'm out on course with it? These are the kind of questions that have been keeping me up at night and I was hoping to get some feedback from current Miata owners.

Former NC owner here.

The NC was only available in 2.0 in the States.

If you're keeping it in Street class, then get a 6 speed with the limited slip, which comes packaged with 17x7 wheels. 5 speeds didn't come with a limited slip from the factory and have 16x6.5 wheels. If you're planning on STR class, then I'd go for the 5-speed, then upgrade the diff to a limited slip. The exception is the MS-R package that was made available for the 2007 model year, which is based off the 5-speed and comes with a limited slip and 17x7 wheels along with upgraded springs, sways, and extra chassis bracing. It's a pretty amazing package for a Street-class car, but you either have to build one or find one for sale from another racer. They're pretty rare and are a class up from the standard models.

Overall, the NC (2006-2008) has a lot of body roll and not a lot of steering feel, but the best upgrade while staying in street class is to upgrade to Bilstein Sport shocks. Pretty much transforms the car while keeping it Street class legal.

In 2009, Mazda made some minor changes to the suspension to increase steering feel and lower the CoG slightly along with raising the redline along some other minor changes. The 2009-present are the ones to get, IMO, but if price is a factor, get a 6-speed 2006-2008 with an LSD.

Other than that, they're as reliable as any Miata, which is to say very reliable. Just beware of the 1st-2nd gear crunch in 2006-2008 model years.

I have a 2006 grand touring for sale. It was my autocross and daily driver.

It has the bilsteins Leonard was talking about and a front bar from racing beat and bfg rivals with plenty of life left. It has the 6 speed trans with the limited slip diff and the 17 inch wheels. The car has just over 40,000 miles on it. If your interested pm me.

It was a fun car and I would countinue to run it but I just bought in rx8. We just had our first kid so we wanted something with a back seat.

I guess I forgot to mention some things. I was mainly planning on staying in c-street for the time being since I'm still quite new to the sport but I would like the idea of keeping my options open and going into STR later on. Is there any particular reason why the 5 speed is better for STR as opposed to the 6 speed? Also what's the 1st-2nd gear crunch in the 06-08 models?

Another thing that I've heard is that some Miatas require 3rd gear more often than others depending on the year and I was hoping to hear more about that if anyone has any info. Finally, I may have a budget of about 10k if my finances are properly planned between now and the start of next year, which I think will definitely limit me to the early NC models.

Also thank you all for replying, this is really helpful.

Max Guijarro wrote:I guess I forgot to mention some things. I was mainly planning on staying in c-street for the time being since I'm still quite new to the sport but I would like the idea of keeping my options open and going into STR later on. Is there any particular reason why the 5 speed is better for STR as opposed to the 6 speed? Also what's the 1st-2nd gear crunch in the 06-08 models?

The 5-speed has longer gearing and you don't have to shift as much for autocrossing, which is why you would want it for STR. The 5-speed NCs only come from the factory with open differentials, but you can add a limited slip differential according to STR class rules. The LSD allows you to better put the power down in corners, while in C-Street, you would be stuck with the open diff because C-Street rules don't allow you to change out your factory diff.

The 6-speed was offered with an available factory limited slip differential depending on the option package. You want an LSD for autocross with a Miata, especially in Street class. While the gearing is shorter and you may have to shift several times on some courses, having an LSD will allow you to put all that power down effectively when autocrossing.

Another thing that I've heard is that some Miatas require 3rd gear more often than others depending on the year and I was hoping to hear more about that if anyone has any info.

The amount of shifting is dependent on the course and whether you have a 5-speed or 6-speed.

Finally, I may have a budget of about 10k if my finances are properly planned between now and the start of next year, which I think will definitely limit me to the early NC models.

That puts you in the 2006-2008 year range.

To sum up:

From the factory:
5-speed, no limited slip, 16x6.5 wheels
6-speed, may or may not have limited slip depending on the option package (if it has the original Bilstein yellows, then it has the LSD), 17x7 wheels

Recommended NC for STR:
5-speed, no limited slip because you can upgrade in STR

Recommended NC For C-Street:
6-speed, factory limited slip

Recommended NC For B-Street:
2007 MX-5 MS-R package (5-Speed with limited slip)

A budget of 10k you say? I have a C-Street '07 RX-8 with a fresh engine for sale for just that price. More power, more fun! And a great car for STX (an RX8 won nationals last year) if you want to move up to street touring class.

Autotrader link if you're interested: http://www.autotrader.com/cars-for-sale ... 6830&Log=0

Just a few additions to Leonard's post.

In 2006 the LSD was a stand alone option so you may find it on a car without the sport package. Later years it was only bundled together. The sport package also has a different part number for the rear sway bar. I think its one mm larger for what that's worth.

The stock early nc's 06 to 08 bilstein's are really under damped. The stock black Tokico shocks are stiffer. The aftermarket Bilstein HD's are the stiffest as dyno'd by fat cat motorsports. I have the aftermarket Bilstein HD's and think they are fine for street use.

The 6 speed is short on gearing. I had to shift alot. Most of our courses had at least one up and one back down and you'll ride the limiter often. 2nd tops out at just about 52 give or take. Some events the gearing can really be an issue with 2nd being too short and 3rd too tall. You get use to it but it can be frustrating.

Jeff Stuart wrote:A budget of 10k you say? I have a C-Street '07 RX-8 with a fresh engine for sale for just that price. More power, more fun! And a great car for STX (an RX8 won nationals last year) if you want to move up to street touring class.

Autotrader link if you're interested: http://www.autotrader.com/cars-for-sale ... 6830&Log=0

Thanks for the offer, but I have a feeling that getting a RX-8 will drive me to the poor house faster than an expensive mistress.

And with that, I'd like to thank you all for your input and wisdom. I now have a better idea of what to expect and look for when I finally go out and purchase my Miata in the near future.

"In 2006 the LSD was a stand alone option so you may find it on a car without the sport package."
Indeed. ANY 06 could have had the diff added, so you can have a 5-speed/LSD combo in any trim level that year, so you could buy a base bucket (5-speed) car and add the diff.

I'll tell you what, if you're not looking for national championships (and you would need an S2K for that) then STR is the place to be. I built a regional winning car out of my 3rd Gen. Limited luxo-boat using a conservative setup, and every mod I did made it a more fun street car too. The guy who bought it from me is happily using it as a daily driver.

If you're going to run stock (street) class, then buy yourself an NB Miata with the sport package.

Steve Lepper wrote:"In 2006 the LSD was a stand alone option so you may find it on a car without the sport package."
Indeed. ANY 06 could have had the diff added, so you can have a 5-speed/LSD combo in any trim level that year, so you could buy a base bucket (5-speed) car and add the diff.

Not true. I used to own a 2006 5-speed and couldn't get an LSD. The LSD was only available through the Suspension Package that was on the Sport and Grand Touring models (both 6-speed) and was never an option for the 5-speed Club Spec or base models (both 5-speed). You can see it in the 2006 brochure linked below.

http://www.miata.net/faq/brochures/2006 ... ochure.pdf

The only 5-speed NC that was ever "made" with an LSD was the 2007 MS-R. Otherwise, you would have seen a lot more NCs with 5-speeds and LSDs in stock class in autocross.

https://www.google.com/search?q=5-speed ... gws_rd=ssl

Leonard, next time you're at the shop I can show you the documentation.

Steve Lepper wrote:Leonard, next time you're at the shop I can show you the documentation.

I edited my post above with a simple Google search, but I'm more than happy to see the documentation you have.

Leonard Cachola wrote:having an LSD will allow you to put all that power down effectively

All that power…

Kurt Rahn wrote:

Leonard Cachola wrote:having an LSD will allow you to put all that power down effectively

All that power…

Relatively speaking - it does have more power than my car.

Leonard Cachola wrote:

Kurt Rahn wrote:

Leonard Cachola wrote:having an LSD will allow you to put all that power down effectively

All that power…

Relatively speaking - it does have more power than my car.

Believe me, I'm not throwing stones!