Input Help: Choosing autoX/HPDE only prepped BRZ/FR-S or ND MX-5

[dowroa]

Hi all!

The Ask:

The purpose of this thread is to understand why those here chose (or would choose) the BRZ platform instead of the ND MX-5 platform, from a performance (and not cost) perspective.

Since the car will be fully prepped for STX/STR (SSC), I am going to ignore any of the stock issues and only focus on a fully, Nationally prepped car.

If you have contemplated both or done both, please share!

Background:

I am fortunate enough to be in a position where I could pick up a 14-17 BRZ or ND MX5. There is no other use than DD/AutoX with up to an STX/STR setup on either.

I haven been on hiatus for about 10 years from autoX. I am ready to return, and either platform would be a great, cheap, affordable solution to jump back in.

I keep going back and forth between these two, as they are both great choices.

As a note, I have a c5z06 for HPDE that I am just not ready to autoX/full prep yet for HPDE. Also, it is just plain expensive to run full time.

So, this MX5/BRZ is my "beater", if you will.

Below, I will just give my view of each. If you have any other input to help a consideration, please let me know.

Class:
STR/SSC/STX

ND MX5:
+ Double A-arm suspension (dynamic camber gain)
+ Factory adjustment for camber/toe on all 4
+ Parts and tires are cheap!
+ Cheaper used, with less miles
+ Light Weight!
- No back seat. Will need a tire trailer
- Open top. I will need a Blackworx bar for HPDEs
- I would personally have to get a hardtop cover for this.
- Broomstick consideration, but known workarounds + rollbar can make this a non-issue
- Transmission BOOM still?


BRZ (w or w/o PP):
+ Can run SSC spec!
+ Sounds badass with UEL (STX)
+ Back seats that fold down
+ Awesome community
+ Slambar solutions for towing rock
+ Aftermarket + Parts are reasonably priced
+ I have literally had 7 Subarus. I know my way around them.
+ STX/SSC at the track == L.O.L.
- torque dip that just doesn't quite go away without a retune
- macpherson struts that have dynamic camber loss issue requiring lots of static negative camber
- need camber plates due to crap factory adjustment (STX)
- changing plugs on this thing sucks
- stock sounding EL (SSC)
- a little more expensive used for a good 14-16 example BRZ

Closing:

Please share any anecdotal stories or inputs you have. Especially if you considered this.

Thank you!

[dutchman1]

Can you pass the broomstick test in a Miata with a rollbar and a helmet on?

Might make the choice easy if you can't.

[dowroa]

Originally Posted by dutchman1

Can you pass the broomstick test in a Miata with a rollbar and a helmet on?

Might make the choice easy if you can't.

Understood for choice elimination.

For the scope of this conversation, let's go with yes.

[14stu]

I thought a used twin would be cheaper than an ND, especially since the twins go all the way back to 2013.

If you go STX, the torque dip can be completely removed with a header and a tune.

I have a great time with my STX BRZ at autox and on the track. I love throwing everything in the trunk and not needing a trailer (I live in an apartment and couldn't do a trailer, which made the decision for me).

If I were starting over, I'd probably do an SSC BRZ or just reproduce my STX BRZ. I think the ND is only the way to go if you are staying in one of the stock classes. Having a coupe and not having to worry about all the different club's convertible rules is nice.

I do about 12 trackdays and over 30 autocross events (many with a co-driver) every year. My BRZ has held up great and has been ridiculously fun. I don't think an ND would be any worse, but I don't think it'd be any better either. The added practicality and daily drive-ability of the BRZ (especially since I am limited to just one vehicle) made it a no-brainer for me, but everyone's situation is different and I see the ND as our low power, light weight, rwd brethren.

You can't go wrong with either.

[Hades]

I've heard lots of reports of the ND transmission failing for those who track the car. They seem to have updated it a few times, but there are still failures. Just something to keep in mind. Not saying our transmission is perfect, either, but the NDs is reportedly weaker. Something intereseting I've found is the Fiat 124 uses the NC transmission. Honestly, that's the car I'd go with if I was looking seriously at that platform, turbo lag issues aside.

Also, a used FRS/BRZ is still quite a bit cheaper than an ND when I last looked. Not to mention the base ND doesn't even come with a LSD.

Lastly, the practicality of the FRS/BRZ is *immense* when compared to a two seater convertible. I can fit all my tools, spare tires, and more in the back of my FRS when I go to the track. Something to be said for just jumping in the car with all your tools & helmet already ready to go when you're itching for a track day.

Personally, I see the ND as the better around town DD or weekend cruiser (more torque, convertible). The twins are the much better HPDE choice stock IMO (more practical, quieter on the highway, more power, coupe, base LSD).

That all being said, I still have recurring dreams of a red ND miata in the same garage as my FRS

[Hades]

Also, you'll obviously get biased answers here. Make sure to post on miata.net if you haven't yet.

[dowroa]

Originally Posted by Hades

Also, you'll obviously get biased answers here. Make sure to post on miata.net if you haven't yet.

Of course. I had originally written it from a BRZ perspective, but forums don't always have owner of that brand on there.

Thanks!

[strat61caster]

Originally Posted by Hades

Not to mention the base ND doesn't even come with a LSD.

Since OP would be building towards STR the base model is more attractive as he is likely already budgeting for an aftermarket LSD, throwing out the OE suspension, and maybe even aftermarket brakes to cut maximum weight. So basically throwing out everything that costs extra on the higher trim except the infotainment, which he won't want because of weight. Base model wins in this scenario.



My 2 cents, the ND will be sharper when tuned, being 300-400 lbs lighter with just as much torque, just as much tire, much better suspension dynamics, and less front heavy. A downside is you'll be forging a new path, I don't think the ND has been really developed for STR yet, a few working on it, but nothing clear cut in the way of "oh do this, not that" to get up front.

The 86 is a good all-around car, but it's no pure sports car like the Miata or Corvette.

Speaking of the Corvette, if it's not seriously modded why not just pick up a set of autox wheels and tires and run it in AS? But from the sounds of it, the car might be modded out of class already so that's understandable to not be on the table.

[dowroa]

Since OP would be building towards STR the base model is more attractive as he is likely already budgeting for an aftermarket LSD, throwing out the OE suspension, and maybe even aftermarket brakes to cut maximum weight. So basically throwing out everything that costs extra on the higher trim except the infotainment, which he won't want because of weight. Base model wins in this scenario.

My 2 cents, the ND will be sharper when tuned, being 300-400 lbs lighter with just as much torque, just as much tire, much better suspension dynamics, and less front heavy. A downside is you'll be forging a new path, I don't think the ND has been really developed for STR yet, a few working on it, but nothing clear cut in the way of "oh do this, not that" to get up front.

Bingo. Didn't realize the car development/maturity was still not there for STR trims.

I prefer to run ST* trims so I can get enough rate and reduce camber loss to avoid chewing tires/flipping tires on rims. I just have never been a fan of doing that.

Originally Posted by strat61caster

Speaking of the Corvette, if it's not seriously modded why not just pick up a set of autox wheels and tires and run it in AS? But from the sounds of it, the car might be modded out of class already so that's understandable to not be on the table.

It is a 8900 mile 100% stock 2002 z06. I still need to do the valve springs and I was planning on a good 18x10 setup square (rears on front) in CAM-S. Tires for CAM-S or Stock tires in AS are about 1300-1500.

For the time being, I would like to not smash it into cones, until a get a few more miles under it.

Just personal preference.

[Hades]

Originally Posted by strat61caster

Since OP would be building towards STR the base model is more attractive as he is likely already budgeting for an aftermarket LSD, throwing out the OE suspension, and maybe even aftermarket brakes to cut maximum weight. So basically throwing out everything that costs extra on the higher trim except the infotainment, which he won't want because of weight. Base model wins in this scenario.



My 2 cents, the ND will be sharper when tuned, being 300-400 lbs lighter with just as much torque, just as much tire, much better suspension dynamics, and less front heavy. A downside is you'll be forging a new path, I don't think the ND has been really developed for STR yet, a few working on it, but nothing clear cut in the way of "oh do this, not that" to get up front.

The 86 is a good all-around car, but it's no pure sports car like the Miata or Corvette.

Speaking of the Corvette, if it's not seriously modded why not just pick up a set of autox wheels and tires and run it in AS? But from the sounds of it, the car might be modded out of class already so that's understandable to not be on the table.

Gotcha. Not familiar with the rules of Autocross, just coming at it from a stock vs. stock perspective. I'd expect a modded ND to be faster than a modded twin, but the transmission issues still worry me.

[strat61caster]

Originally Posted by dowroa

Bingo. Didn't realize the car development/maturity was still not there for STR trims.

I don't think it's even firmed up for the 86, there's still some radically different suspension setups floating around and only one or two off the shelf that seem viable without a whole lot of homework to do. The rest is kind of 'choose your flavor and budget' but the suspension tuning is still wide open imo.

If your head is in autox it seems like everyone is doing it, but right now I don't think anyone offers a 'kit' off the shelf to be competitive in STX, at least not one I would buy, and I haven't seen evidence of that existing for the ND either.

[dowroa]

Originally Posted by strat61caster

I don't think it's even firmed up for the 86, there's still some radically different suspension setups floating around and only one or two off the shelf that seem viable without a whole lot of homework to do. The rest is kind of 'choose your flavor and budget' but the suspension tuning is still wide open imo.

If your head is in autox it seems like everyone is doing it, but right now I don't think anyone offers a 'kit' off the shelf to be competitive in STX, at least not one I would buy, and I haven't seen evidence of that existing for the ND either.

Fair enough, and that is why SSC had a certain appeal to me (other than not being able to run a '17+, which I liked those cars but understand why not).

It limits the variables and the spending. From there, the adjustment is somewhat limited (other than "oh, the strut came pre-bent at -3.5*) and a good place to re-enter.

That, and the spec tire (to be announced, IIRC).

Thanks for the insight. That is kinda what I need for being out of it for so long.

[Imp]

Hey Dowroa. (Same one from NASIOC of years ago?)

Anyways, I went with BRZ because I fit in it. Can't make a miata work. So, I also just bought my FRS for SCC next year. I think it's going to be a hit running against other drivers with minimal differences... the discussion will just be about alignment settings and tire pressures, not "they have XYZ car, so it's just better".

Show up and drive knowing a) you didn't bring a knife to a gun fight (underprepped vs everyone else) , or b) you didn't bring a gun to a knife fight (overprepped and get called a cheater).

Come on in! The water's fine!

--kC

[dowroa]

Hey kC! The same... just older with kids and a mortgage.

I agree, logically, with the FRS. Same car. Less weight. Best of min/max.

I am just weird and want something that says "Subaru" on it.

I think it will take me a little while to get a car and be prepped fully, but I agree with the SSC choice.

Just exploring options, getting input, and ensuring I didn't miss anything first.

Glad to see you online and maybe I will see you again in the future!