As a continuation of this thread: https://www.miataturbo.net/race-prep...0-85778/page2/
Id like to focus my attention on figuring out the exact suspension differences between the 2 platforms.

I have been keeping an eye out for an NB, but found a pretty good deal on a NA.

The front subframes ared different, that much I know. Since Im doing a swap anyway, an aftermarket subframe will take care of the differences there.

Are there any differences to the spindles and hubs?

What about rear suspension?

Thanks again.

David

 

tophats, springs, perches.
do a search I'm pretty sure there's a really detailed thread about it.

\/ or just look below \/

 

If I recall correctly:

• NB subframes have the lower control arm mounting points dropped for geometry correction
• The tie rod points on the spindle are raised for bumpsteer correction
• The UCA balljoint taper angle on the spindle is different as well, but aside from the different balljoint, the upper arm is the same as the NA
• The NB uses a unique steering rack mounting.
• In the rear, the spindles are a little different which gives a 5mm wider rear track width on each side. The subframes, arms, etc. are all geometrically identical
• The NB lower arms front and rear only have a single-shear mount for the sway bar links (NA arms have double shear mounts)
• The rear subframes have different locations for the exhaust hangars
• The tophats locate the shock shaft higher in the chassis (allowing for more bump travel at the cost of droop travel, all other things equal). Most aftermarket shocks are set up for NB tophats.

As far as I know, that's it.

 

Thats awesome.

Im not overly concerned with the easy bolt on stuff like hats and springs as I planning on getting coilovers and most likely suspension arms for it.

The single vs. double shear is an interesting observation.
The S1 and S2 Elise had a similar situation although Im surprised the Miata went backwards.


What about ABS?
is it worthwhile to swap the later ABS unit?

D

 

yes. NB2 abs setup

 

If you plan to run in the rain, sure. Running production-grade ABS in the dry is a recipe for torched brakes and longer braking distances, though.

 

Pretty much what everyone else said... since you'll be swapping front subframes anyway for your motor swap, half of the car can be "as you wish". At least up front.
Since this is going to be all "racecar" and everything, the NB2 abs swap will be very advantageous. And a heck of a lot cheaper than say... caging an NB2.

 

I'm not so sure. If you're looking to do a swap, buying a high-miles NB2 with a straight body will be far less of a hassle than buying an NA for less money and then trying to transplant the NB2 ABS into it. Not to mention the NB2 running gear is worth more.

 

There's nothing wrong with a single sheer solution as long as it's designed properly. The e-famous one is the Lotus toe link, but the issue wasn't that it was single sheer; it just straight up wasn't spec'd properly.

 

The front upper control arms are dimensionaly the same, but the NB control arms have more gusseting on the lower side compared to the NAs. It actually changed at least three times between 90-05 from what I've seen. NA6 had the least (mostly around the bushing tubes), NA8 got a little more (extending away from the bushing tubes), and NB got even more (out towards the middle of the control arm).

 

Thank you.


I will probably go with a complete set of lightweight aftermarket A arms, so not overly worried there.

From what Ive gathered so far, most of the changes were up front and aftermarket subframes are modeled after the NB geometry anyway.

Rear suspension seems to be mostly the same.

Aero is pretty close after a wing and a splitter.

Only big differences are the ABS (which Im researching now)

Fuel system is different too: NA is a return system where NB is a returnless (like the K series)

So the NB has many advantages:
Slightly better aero
Easier conversion
ABS

Also some disadvantages:
More expensive to start
Fuel system is harder to modify later
Heavier

NA advantages:
Inexpensive to start
Lighter weight

Disadvantages:
More complex conversion
Needs a fair bit more work
Not as good aero (some of which gets negeted by more power and aero development)


Thats what I got so far....

*edit* as per Andrews post, I will investigate the differences in hubs and spindles as well.

 

If you look you can find NB's for under 2K that need some work. A friend of mine just got a '01 from under me for $1500 with a "bad" motor.

All of the ABS hubs I've seen have been the same and have less stress risers than than NA. All the NB (ABS and non) I have seen look to be same just with and w/o the tone ring. We make it a point on our Chump Car to us ABS or NB hubs exclusively for the additional strength.

 

Apologies to bring up an old thread but I couldn't find this answer anywhere.

As part of the suspension refresh I am doing on my NA Turbo (which I will make a build thread on once I've got some spare time back after I've got the car ready for this trackday), I thought if I'm going to install ABS sensors (for datalogging and MS3'ness), then I may as well do that now if I'm buying new hubs and ball joints etc. To that end, I have bought ABS uprights which were allegedly from an NA. However, my search results appear to say otherwise.

For the front, the differences I have read is that the NAs have a thinner ball joint taper flange and a lower outer ball joint mounting flange height. My old NA hubs measure just over 14mm thick (9/16") in the upper ball joint location and the ABS NA hubs measure just over 18mm (23/64") thick. Am I right in thinking that the ABS hubs I have are definitely from an NB and that there wasn't a year of NA that had ~18mm thick upper ball joint flanges? The outer ball joint height change is difficult to eyeball, but that also suggests my ABS hubs are NB.

For the rear, the difference NA to NB is more subtle, with just a 5mm offset increase from NA to NB. Is there any way to tell these apart other than measuring this? With a spirit level and a tape measure, this isn't an easy measurement to make. Regardless, if someone has measured it, I get ~147mm axially from the face of the hub to the centre of the upper bush on the ABS hubs and ~142mm for the same measurement on my old NA ones, suggesting that the rears are also NB (or I'm terrible at measuring)