About to buy some Konis for 95 Miata. Will be using them with ground control coilovers. I hear that 9mm spacers need to be used with the NA Konis and that the NB konis do not need these spacers. I know that the NB Konis dont have adjustable perch heights like the NA ones do but thats not and issue cause ill be using the ground controls. I plan on running NB mounts or possibly the ones from ISC racing Id like to run the NB konis to avoid needing the 9mm spacers. I cant find any info on NA vs NB konis and how different they are....do the NBs have a longer body to them ? NA or NB konis...what should I do ?

I'm curious as well about this.

both are konis, so both suck?

it's funny that in other car circles, Konis are looked at as a good damper choice. In fact i know one national champ (sam strano) that races f stock and owns a part shop that recommends Konis over coilovers in the Mustang world. The miata guys seem to hate them though. why are they so frowned on in the Miata circles?

cause they suck? and were developed for the miata with stock spring rates in mind about 22 years ago when the fastest miata is slower than the slowest turbo miata?

Haven't ever known a Mustang to be noted for good handling...
But to answer your question, Konis are frowned upon for a number of reasons.

1: The compression damping is designed to work on stock springs, and that's about it. So once you start turning up the rebound damping to handle higher spring rates you end up "jacking down" onto the bumpstops because you can't increase the mid-speed and high-speed compression damping even a little bit to counter the effect of the extra rebound damping.
The result is a crap ride, horrible grip, and handling that only an uninformed autocross driver could love.

2: Twin tubes = suck.

3: For the money it would take to buy new Konis and send them in to an authorized dealer to be re-valved and to get a ground control kit with the spring rates you want, you could invest in a set of FCM coil-overs or the Xida CS coil overs for basically a few dollars more.
So why waste time on a twin-tube that actually does nothing better than it's mono-tube brother even after it's been rebuilt and re-valved?

4: Twin tubes = suck.

thanks for the more technical answer. some Mustangs can handle very well, the Boss 302 was very capable. granted different cars than the miata. Mostly i ask because the track car i bought has Koni and ground controls, apparently several cars like mine were built in an attempt to start a turbo spec miata class so they are using spec style suspension. just curious why they seemed to be universally disliked on this platform.

Koni gc is so 1996

Jeff, I understand you have a lot of experience but I'm not sure that I agree with your opinion regarding compression. My SD Billies have only about 50# of compression but maybe they act different than a Koni due to being a monotube. And I haven't driven a Miata with Koni's.

dont.