Should I move to a turbo NC?
 

I'm considering building an NC:

- ~300 whp trackable turbo street car with built 2.3 or 2.5 L
- rollbar for track
- maybe a PRHT?

Advantages to me, in this order:
- chassis rigidity (better NVH)
- displacement
- tire width
- better rear supension geometry?

Cons:
- looks - that hood line, and the headlights, are ugly
- cost of building?


Now my questions are:
- Can the tranny and diff take 250-300 ft-lbs for HPDE's?
- Does it have the crappy gear ratios of the NA/NB 6-speed + 3.9?
- Has anyone installed a full standalone? in parallel? What issues are there? CAN?
- Are there good cooling solutions with AC in place?
- Why don't FM make a turbo kit for it? I'm a bit leery of BEGI fitment issues

Rear suspension geometry, being multi-link, is superior. How much better, no-body is really talking, although I'm sure you could find the info. The NC chassis is essentially a shortened RX8. They're also inherently heavier (see good-wins build).




As for tuning, ANY car can run standalone, it's just a matter of how much of a PITA it is to get running. Most of the boys at M.net, are still "flashing" each other.

I vote for: Yes, do it
Because I know you can pull it off. And would probably put together a well sorted NC.

And there's nothing wrong with "flashing". I really enjoy tuning modern sophisticated OEM ecu's that have most of the hard work done for you and you just tune the fun parts.

If i could afford it, I would. NC is a neat car, and I love the way they look tastefully modded.

For a track car, i'd still stick with na/nb though.

OH
Yes
Oh Yah
YES YES YESSSS

Yep, I think it would be a pretty good idea.

Another yes here. I'm not crazy about the NC's appearance, but if modded right I think one could look good. And while a bit heavy, they're very nice cars. You get a lot of plush for the extra pounds.

The one thing I like about the extra plush is the bigger gains you get when you get rid of all that shit when you end up building a track slut.

I would probably never get the PRHT personally.

I'm loving my NC. A few things I've learned second hand. First, a built 2.5 with cams and all the supporting mods gets close to 300whp without the turbo. NC light has 270 whp, and dynotronics is working on a 2.7L variant which should put you right at 300 hp N/A. If you must have a turbo, I would just stick with a built 2.0, or else do a full N/A build for the same money. Flashing the ecu really is like having a standalone. You are just reprogramming the factory maps instead of an MS, it's the best of both worlds. For a track car, I'd be looking at a roll bar and soft top, the prht is heavy. From what I've read, cooling isn't much of an issue. A bigger radiator pretty much does it. The radiator is fitted on an angle similar to the rx7 and the factory ducting is light years better than my NA was. The 6 speeds are supposedly stronger, but I dont know how much. The gearing is also crazy close together. I drive between 3-4k as standard shift points and I shift every 10 mph or so. I'm sure there are beefy gears available though for the 5 speed. Don't know about the diff, but the v8 swap kits are out there making that diff a last resort. All that being said, I really love this car. Same miata spirit, but more refined. It's like a comfy miata for adults rather than the no compromise go kart that my old one was.

There is when the "tuners" have no idea what they're doing.

The Luddite asks a genuine question:

Does anything similar to RomRaider exist for the NC's ECU?

You mean like TUNING DONE RETARDED?

:giggle:
Yes, its called ecutec and they bend you over and penetrate with no lube for the "license" to use it.
If opensource/affordable solution existed for teh NC I'd probably be selling my NB right now.

So, that would be a "no," then.

I guess that my next ECU question was answered.
No easy-to-tune, on-the-fly tunable, affordable, reflash software.

Yes, this is all doable. As for affordable, the delta force tuner is $700. I don't know how it compares to ecutek. Obviously, open source would be great, but I wouldn't say it is going to break the bank either.

$700 wouldn't be too bad if it's easy to use, and doesn't waste time while tuning at the dyno.

700 is just for the hardware with which you can flash, not the ability to tweak anything.

Like I said, no lube.

"Commando Package is the most comprehensive tuning software package for the 2006-2008 NC MX-5 Miata. This software allows YOU access to ALL of the timing, fuel, MAF, torque, throttle, open loop, rev limit, and idle tables/functions. This is what you will need to make the car run reliably with forced induction or for highly modified NA vehicles. It includes the interface box, cable, and software. "

Complete MX5 Miata Tuning Kit- Delta Force Commando Package with FULL SOFTWARE CONTROL for MX5 2006-2008

Not what I think it is? This is on my list of things to buy, but maybe I should reconsider if I can't tweak it myself. :dunno:

The NC chassis is light years ahead of the NA/NB, the top is better, the engine is better, but I don 't know about the transmission or rear diff. DO IT.

is it?
how so?

genuinely interested

Personally I would want a LS1 RX8 using the v8 roadsters kit, but a 300whp NC, mazdaspeed front bumper, hardtop, wide wheels, AST, and 300 whp NA would be really cool

I'm sure you know it is a topless, shortened RX8 chassis. It is a lot stiffer and the wheelbase is longer, so the ride is better.

I drove an 08 and the MSM I ended up buying back to back on the same day. The MS has all the factory bracing possible, but the NC still felt way stiffer. The ride was also smoother. I also like the torque of the 2.0 it has. I was attracted to the turbo, but I genuinely wish I would have picked up the NC instead.

The RX8 rear suspension is very complex. If that is what it is then I am a little concerned. Somebody had said that the 5-speed was weak and failed if you bump the power much at all. I think it came up in that other thread that MX George was offering info in. The one with the BEGI verses the blackone guy.

Why is a multilink rear better than A-arms?
Don't racecar designers use A-arms even if the rules allow multilink suspensions?

Because it allows for more compact packaging and, if so designed, can also permit independent adjustment of each suspension parameter (camber, caster, toe) without affecting the others.


Those which are not space-constrained often do, owing to the greater simplicity of the A-arm design.

Many of the higher-end car makers (Lamborghini, Porsche, Ferrari, etc) are beginning to utilize multi-link designs, as are some classes of race cars (Baja, certain rally leagues, etc) in which the benefits of the design justify the added cost and complexity.

Toe gain as well as camber gain under compression, significantly lighter, better packaging.

No... Albeit, it's habitable, a miata is too small a space to live inside of. It would be better to move into a place with a roof.

my :2cents:

also, 69th post ftw.

Do it I need some more NC mt.net friends!

Goodwin is running a standalone, but its Motec. Ecutek flash with Racerom is a pretty good option, has switchable maps for e85 and some other options that catch it up to the new series of standalones. I would probably say get a soft top since the roll bar options fit better with the soft top, and it is lighter. If you are really going to track it often, soft top. If you will track less than 4 times a year, prht.

And I think the gear ratios are still pretty bad.

You should OP. And I have a cream puff of one I'm looking to sell between now and spring.

'06 Grand Touring (bose/leather/6spd), sport package (LSD), 43k miles.

/spam

Kind of curious about this myself.

FM say in a nutshell:
- expensive, expensive to develop, requires fab work to install, small market, and the sc kit they sell is well-developed and already makes the max power the stock motor can take

Given the expense I may make the move only if a turbo'ed rollbar'ed one showed up for sale.

fixed^

You have one for sale?

I'm also now wondering about a 320 whp turbo S2000 setup....

Make sure that you actually go out and drive an S2000 for a long distance before getting too attached to the idea. It's a very well-built and well-mannered car, rigid as a girder, great suspension, excellent transmission, tight and responsive steering...

...and a hideously uncomfortable place for humans larger than a Japanese schoolgirl to spend any length of time sitting in. The NA's interior feels like a Lincoln Town Car as compared to an S2k. There's a reason that they didn't sell well.

last one I drove, an 06, felt like it was super narrower than a miata inside and actually felt more cramped than my nb.

it also felt less torquey than my stock nb.

they also get crap gas mileage, but that's off topic

I loved the S2000s I drove, I'm also 5'7-8". Much better car than an NC. I only bought an NC because an equivalent condition/Mileage NC was 60% of the cost................for a reason.

And I can believe this. You are literally the exact same height as an average Japanese 17 year old male.

(source: Template:Average height around the world - Wikipedia, the free encyclopedia)

A former co-worker of mine (who is also below the US national average height) owns an S2K, and I have driven it on two occasions, and ridden as a passenger on many more. It is a well-designed, well-built car. It merely happens to have the most cramped interior of any motor vehicle since the Mercury space capsule.


https://www.miataturbo.net/attachmen...ine=1386298633

Total buzz kill.

Interesting input on the cramped cockpit. However I'm the same height as the prototypical 17 yo Japanese male and 155 lbs.
The door bars in my NB made it feel significantly narrower...

Can anyone comment on the chassis rigidity / NVH of the S2000 vs the NC?

^ Something I never understood...

I was in the market for an s2k until I got in and out of one a few times. I threw my wallet in the back of the car and alas, there was no more room for anything else. My father has an 02 however he is 5'7" 140lbs. Had a friend tell me a while ago to get a miata and fought it until a work buddy let me inside of his. I am still surprised how roomy a miata is for it's size. Even more surprised how roomy the trunk is. I'm 6'0" and 205lbs and I even have to move my seat up a little to fit well. The only complaint I've had is I wish I had tilt steer, but only because i'm too lazy to lower my seat or cut foam.

Use fender washers for tilt wheel.

I never had any problems with size/comfort in my S2000 (FWIW I'm 5'10" 160lb) and gas mileage was very reasonable. Mine was supercharged 325hp, 200tq and it would get 21 around town and 28 on the highway, my turbo miatas have gotten 23/28 with similar driving.

I did destroy a lot of drivetrain parts though; blew up 2 rearends and broke 2 driver's side axles in a short time. I've easily logged 3x the mileage in similarly powered miatas without breaking anything. A lot of that was drag/launch related damage so it might not be as severe in a trackcar, but something to be aware of at least.

https://www.miataturbo.net/attachmen...ine=1386346960

https://www.miataturbo.net/attachmen...ine=1386346960

The only NC I've ever driven was one of the original pre-production mules back in '05 or thereabouts, so I can't really make a comparison, however the chassis of the second-gen S2k is unbelievably good. You get none of the squeaking / rattling noises from body flex which define the NA and NB. The top is also excellent, and doesn't cause much in the way of wind noise when up.

It's an extremely well-refined car, as is typical of the brand. It's just got a very oddly designed interior, with lots of bumps and protrusions, and controls located in nonintuitive places. Think Lotus Elise.

I was searching for an s2k when I bought my NC. The ap2 s2000 really is a fabulous car. The big difference I noticed about the interior is that the door comes up much higher on my shoulder and it makes it feel like you're sitting down in a bathtub or something. It's strange, like the car engulfs you. It doesn't bother me too much, as I still love that car. The 2 big factors that won me over for the NC was the price first of all. There was a $5k difference between my NC and an AP2. I didn't even consider the AP1 for many reasons. The second was the low range torque. While the miata has less power, the low end torque really is fabulous. It is a drastic improvement in drive ability and around town driving over the NA/NB. Once you get that f22 motor spun up, it's a blast, but driving at 5k rpm just around town is annoying. The interior roominess was a distant 3rd deciding factor.

Ahh, the AP2 S2k. 320whp turbo is conservative judging by hingston's setup.

It's such a wonderful car. But know why it's more refined and rigid than a Miata?

2835 pounds.
Ouch.
That's about 250 more than an NC PRHT.

Edit: says the guy who drives a 3700 lb "performance" car :facepalm:

I think more rigid. the S2000 uses a "x-brace" setup putting the "frame rails" higher in reference to the other parts in the car. Also, they do have structural rigidity in the center (see pic) along with the rocker panels, so they are definitely sorted out well there.

Not sure about the NC chassis, but I am doubtful that Mazda did something comparable. I do have to say the RX-8 has some amazing torsional rigidity numbers (much better than the RX7 if I remember correctly), which you can find freely on google. If mazda was able to carry that over to the NC, then its got a fighting chance.

https://www.miataturbo.net/attachmen...ine=1386382719


With all that said, I think an RX8 is a better choice for a track slut (not sure if that is what you were going for). Rotaries respond well to mods it seems, especially with porting and if you give up on that, they will take a v8 easy. Or maybe go all in for a 3-rotor.

EDIT:

I looked some of these numbers up, they are probably speculative. Also torsional rigidity is not the only factor in chassis stiffness. Bending rigidity is also important among other things...Most people don't post sources on the forum for this but here is a few:

RX-8: 30,000 Nm/Degree
NC: 8,800 Nm/Degree
S2000: 7100 Nm/Degree or 20,000 Nm/Degree (20k seems way too high) (Link1 has both, link2 has 7100)
NA/NB: 6000 Nm/Degree


Lastly here is a discussion about chassis rigidity between NC and s2000 on an s2000 forum.

modding the rx8's rotary engine is the pinnacle of retardation.

v8 or bust

it seriously is one of the best chassis with one of the worst engines. mazda trolled pretty hard with it lol

yea but 3 rotor rotary ftw. Just fuckin do it, I will buy it from you after you spend your life savings shipping one over from a JDM cosmo (because JDM) doing a peripheral port. but it has to be an rx8

Lol - I have a Lotus Elise, and I *still* have to consciously think about the location of the door locking button (front edge of the shifter cover, facing your feet) every time I drive it.. On the plus side, it's about the most minimal modern sports car you can get, mine especially so being an '05 "first year" car before they went to throttle by wire and traction control and all that newfangled gobbledy gook. There really aren't very many "controls" to contend with, and they don't seem so oddly placed to me. Two knobs and a push button for the heat, two push buttons for the lights, a stem for turn signals and a stem for wipers, and the start button. Shit, the radio has more buttons than the rest of the car.

I tend to take numbers found on the internet with a grain of salt, so I'll just say this: There is absolutely no way in hell that a second-gen S2k chassis is only 17% more rigid than that of an NA. I would accept double without flinching, and even triple after I'd done a little back-of-napkin figurin'. But those numbers (6k vs. 7.1k) just smell like yesterday's catch.


At Honda, the chassis is designed by an engineer and then handed to the stylist for polishing. At Mazda, the chassis is designed by the stylist, and then an engineer tries to figure out where to add bracing in order to keep it from collapsing under its own weight.

I love the NA/NB, but they practically define the concept of chassis flex. There are no companies selling the equivalent of Frog Arms for the S2k, and there's a reason for this.

I agree with you, but hear me out:

1) 7000 Nm/Degree seems to be a number a GM engineer came up with in one of the forums. It also is the most commonly accepted number that I have found in the s2k forums.
2) 20,000 Nm/Degree is the other possible number, but no other convertible in the world comes close to that. An Elise is 10,000+ Nm/Degree and its even newer and stiffer feeling than an S2K.
3) I am in no way saying these numbers are correct. I tend to agree with you, my s2k experience says its much stiffer than an NA/NB. I do have to say that its purely a "butt dyno" measurement and we all know how inaccurate that is.

Just wanna say though, despite the little gripes with the s2k, I think its an amazing little car. If they weren't so expensive and pricey to modify compared to the na/nb, I'd probably rock one. They just look so good I admire just about every one of them I see

It's more than a butt-dyno, it's an ear-dyno.

Just think about all the little squeaks and rattles than a stock NA emits when driven over a bump at speed, especially if the hardtop is attached at the time.

The S2K does not make those sounds. I don't mean that they are less intense, they're just not there at all. The chassis isn't stamped and welded together, it's CNC-machined out of a solid block of granite.

To be certain, you pay the price for this in interior comfort. Like the Elise, the S2k door sills are a mile wide and the tunnel was designed using the same technology as that employed in the central span of the Sydney Harbour Bridge. But to compare the rigidity of the S2k to the NA, you can't even use the same units of measure.

I love my NC2, much roomer than my old NB. Nobody has really tested the limits of what the stock (09 and up) engine can take.

Are you comparing your high mileage car to a low mileage S2K? My lower mileage NA never squeaked at all.

My '92 had around 45,000 miles when I bought it in '04, and around 70k when I sold it in '11. I believe that Dave's second-gen S2k had about the same mileage during the time that I drove it, possibly just a tad more (he was commuting to Burbank and back for a while.)

So, no, I think I'm making a pretty fair comparison.

And before you say "well, I'm sure that your '92 was compromised by rust," we don't even know what rust is in SoCal. People use unrestored cars of 1960s vintage with original paint down there as their daily-drivers.

I have never driven a Miata with a hardtop, nor have I spent more than 10 minutes in a S2K. Perhaps I spent way too much time in an MGB to be qualified to remark on what is adequate stiffness.

Maybe I have owned too many GM products, but I'm always shocked at how little my 132k NB rattles or squeaks. For a while the street wheels had no wheel weights and the thing would shimmy like crazy at 65mph, but nothing would rattle. I've never had a hardtop though.

I will be honest with you, I have never driven an NA. I have only driven NB miatas enough to make a judgement. I have not driven an s2k or an elise, but I have plenty of passenger time on track with caged/non-caged variants of both cars.

I can't speak to numbers, but the s2k chassis is definitely light years better than the NA/NB. I don't really know if its better than NC. It seems to me neither Mazda nor Honda have released any numbers explicitly stating their measurements.

The only numbers released by mazda was a % improvement over the NA/NB chassis and apparently Mazda at one point said the NA/NB was a specific number (listed above). I did not find a source for the 6000 Nm number listed for the NA/NB.

What I do believe is that the s2k is not magical. I would not place the s2k any higher than an Elise in chassis rigidity. I do believe there is a significant margin for error here. Numbers are passed from one forum to another, with the original source missing or no longer on the web. Also, many of these numbers are measured differently from one manufacturer to another. Its easy for an interwebz copy to not carry the units. Lastly, it seems the 7.1k Nm s2k number is a CLAIM made by a GM engineer in reference to the solstice (see Link1 which is the most technical discussion on s2k stiffness). the 22k number still has no source (its claimed to be originally found on japanese and korean sites).

I think its plausible (at least to me, based on no actual number stating that and no previous ownership of either car) to say that the s2k chassis is probably no stiffer than an Elise (~10k Nm/Degree)...

Anyways, this topic has been hashed out pretty good. Jason can make his own decision on the stiffness he wants/needs. We should hash out another topic!