Originally posted by Lokiel, Sun Sep 24, 2017 3:48 pmOriginally posted by Lokiel, Sat Jul 02, 2011 6:41 pm[The NB's 6-speed gearbox is known for its ambiguous reverse gear selection and sloppy feel when compared to earlier NA 5-speed gearboxes. I've never been really happy with my SE's gearbox, especially when compared to my previous car, a 1982 Mitsubishi JA Starion. About 30% of the time I need to re-select reverse gear when I don't move or get the dreaded gear crunching and occasionally I select the wrong gear which makes me second-guess each subsequent gear change.
Miataroadster has recently created a Short Throw Shifter for the MX-5 6-speed gear box that has been getting rave reviews on the web so I thought I'd give it a go.
See:
http://www.mazda-speed.com/forum2/index.php/topic,23486.0.htmlhttp://www.mazda-speed.com/forum2/index.php/topic,23531.0.htmlHere's the 2 versions offered (standard height and long version) and a comparison of the long version against the OEM shifter:
Summarised comments from the manufacturer:
*Because of the better design (use of the NA factory shifter's "crescent" bushings on both sides of the fulcrum ball vs. the NB factory shifter's crude metal-on-metal contact with the dowel pins in the turret) and superior manufacturing quality over the factory shifter, with either the tall/angled or stock height version MiataRoadster shifter, shifting will be more precise and predictable (rather than having to "find" the desired gear).
*The stock height version will be harder to shift than a stock shifter, but with a shorter motion.
*The tall version takes the same effort to shift as a stock shifter, but with a slightly longer arm motion.
*We had been using the JDM brass tube angled extensions with a Mazdaspeed JDM short shifter in our race car and snapped off two of them.
*For liability reasons, I stopped selling them and pursued offering a one-piece shaft with the angle built in.
*The benefits of the tall version having the shift knob closer to the steering wheel alone outweigh every other feature, that's the main reason why I got into the short shifter business.
I ordered 3 standard height SSK kits (one for me, MINX and Davex3) and they arrived from the US within 7 days - this also included the actual manufacturing of the shifter. Everything was included except the heavy duty grease for the shifter's pivot ball and selector ball.
Installation was painless, taking only 30 minutes or so in total per kit and the instructions are comprehensive with lots of pictures to make everything idiot proof.
As expected, the SSK throws are much shorter. Gear selection takes a little more effort and is now much "notchier", selecting a gear is very distinct; before my gearbox felt quite sloppy at times. Reverse is much better because of this, I now know that I've selected reverse because you can feel it locking into the notch; before I really never knew.
So far I'm liking this mod a lot and wonder why the OEM shifter was so sloppy/vague, especially given that early 5-speed NA gearboxes were praised for their precision (ie. How can Mazda have accepted a gearbox in the NB that was much worse than the NAs?)
If you're at all unhappy with your 6-speed gear selection, this is a "MUST DO" mod IMO.
Originally posted by bootz, Sat Jul 02, 2011 8:01 pm[Really Simon, you overstate your case.
Six speed reverse is excelllent. I took about a year to get the 5-6 change down pat. A diff change helped.
I can punch any gear I want at any RPM. i.e 2nd to first in 5000 no problem. This is a seriously tough box.
Originally posted by bootz, Sat Jul 02, 2011 8:10 pm[Sorry, re reading I think your box may not be performing like mine. Perhaps manufacturing variations.
I have NO isssues with the 6 speed. Perfect change all the time. I think 5-6 is a little ambiguous, but a firm hand fixes.
Would happily abuse this box anywhere. Now the NB8B clutch is another story strong but shudders, you need to hit it with a stick. Not perfect for a light car.
Love what your doing.
Originally posted by Lokiel, Sat Jul 02, 2011 11:19 pm[bootz wrote:Really Simon, you overstate your case.
Six speed reverse is excelllent. I took about a year to get the 5-6 change down pat. A diff change helped.
:
You my friend have one of the "blessed" 6-speed gearboxes if your reverse is excellent, a LOT of people have issues with reverse on their NB 6-speeds.
Check out this link for other people's problems with the 6-speed gearbox:
http://www.google.com.au/search?hl=en&biw=1138&bih=1053&q=+site:forum.miata.net+%2Bmiata+%2Bnb+%2Breverse+%2BshiftConsider yourself lucky with your shifter/gearbox and know that it's better than most.
I actually found it embarassing when I ground the gears trying to reverse in public places - MX5 owners knew what was going on but everyone else probably thought I was a noob.
I agree with your "firm hand" approach though and that's OK on the road but a track is different. The problem is that you have to think about gear changes too much; once you've missed a gearshift, shifting stops becoming automatic and you focus on them too much rather than other driving aspects.
I'm hoping to get back to not even thinking about gear changes with this SSK. So far, so good.
Originally posted by Hellmun, Sat Jul 02, 2011 11:30 pm[The NB8B and SE gearboxes are not the same Bootz. Travel distances are very different between the SE and normal box, I found the SE box a little notchier but the distance between 3rd and 4th is MUCH shorter (maybe 1" total travel). I personally find the NB8B 6 speed a bit vague from 3rd to 5th on the track and have been looking at making a guide plate it make it much harder to get into the reverse gate for track work. Would love to know if the short-shifter helps in this regard. In high-G corners with the engine cantered like getting onto the main straight at Phillip Island it's a real pain getting into 5th quickly.
In regards to crunchy reverse, I find tapping the 1st gate, dropping to neutral and pumping the clutch twice seems to ease entry when the car is dead cold and remove the crunch. I used to think my stock clutch was sticking when cold but even my new Exedy HDB does it as well. Same solution still works though.
Originally posted by bootz, Mon Jul 04, 2011 1:20 pm[Hellmun wrote:The NB8B and SE gearboxes are not the same Bootz. Travel distances are very different between the SE and normal box, I found the SE box a little notchier but the distance between 3rd and 4th is MUCH shorter (maybe 1" total travel).
Thanks Lokiel and Hellmun. Big news to me.
Hellmun wrote: I personally find the NB8B 6 speed a bit vague from 3rd to 5th on the track and have been looking at making a guide plate it make it much harder to get into the reverse gate for track work.
Your comment parallels mine perfectly. If you have to think about it you are taking too much time. That saying, with the same diff as yours I now get to use the 6th gear on a regular basis.
It is a bit curious actually.
This same box is used in the RX-7 and Toyota Lexus. Only top quality equipment would be used in the Lexus, ditto RX-7.