in for info and updates.

1st and 2nd are the 2 gears that are furthest off ideal ratios but do not fail as often.
What your calling a main shaft is the actually the counter shaft, and there is some hope the existing part will fit.

You may be right actually (forgot these were RWD). This is the expensive part, which has 1st/2nd machined in to it.

http://www.teammfactory.com/assets/i...F-TRS-01GT.jpg

Spare trans came today and I got it 95% apart before having to stop. Input shaft clip is a PITA. Will have pictures and measurements Wednesday.

Service manager at Jacks here - We've built 2 PAR AZ6 'boxes. One was a very early build and PAR fucked up by sending us a Miata version of the gearset...the countershaft was 3mm short but we made it work for a year or so until the 3-4 fork wore out, the 3-4 synchro overextended and shat out a detent ball which went through 1st gear. Amazingly, PAR sent replacement parts at no charge, but mostly because they didn't send the right stuff to begin with. Replacement parts went in last year and the car is making around 480wtq and 550whp. The second set was actually manufactured correctly and everything went together very smoothly with that trans. Guy drove his car over from CA, flew home, flew back over, drove home. Loves it, but he's not making big numbers on it yet AFAIK. Because the incorrect set was sent over for the first build a couple of years ago I'd assume that they can still make them (correctly for Miata). We stopped dealing with PAR directly last year due to some differences in opinion on a couple of subjects but we can still source their gearsets through an intermediary. That being said...

We'd much rather give our money to Mike at MFactory :-) They make a bunch of quality parts for us and are a pleasure to work with, and we've been working with them for years. @MFMike we've never personally corresponded directly as John usually handles everything re: outside sales, but feel free to PM me here if you'd like my work contact info. I'd love to get something off the ground with you guys that could work for both the BRZ/86 and Miata versions of the AZ6. A helical, synchronized gearset would also be our preference.

Our (Jacks) modifications to the 4th thrust problem will certainly bump up the power capacity of the trans but it is not a panacea. We bought a trashed Miata 6spd from BBundy last year for R&D and found that it failed due to 4th synchro gear wandering out of position...our fix keeps this from happening but the teeth are effing tiny on that gear so it's only a matter of time before they snap off under higher load. The 3-4 fork is also pretty much dead in every AZ6 we open, so we have a hard anodized, billet aluminum fork for the BRZ/86...will have to check if it will work with a Miata 6spd. We also have a double synchro 4th gear in beta testing right now, and a 3-4 sleeve detent ball modification (so they are captive and never pop out), and those should translate to the Miata platform as well.

None of that matters if people are still tearing teeth off of gears. If Jacks or the Miata community at large can work out something with MFactory on an upgraded gearset, I'll work on setting up a package deal on installation if anyone wants that to happen at Jacks. Thrust mod/billet fork/double synchro 4th/detent mod + upgraded gearset would be killer.

Awesome!

If Jacks has a Miata gearbox and has already confirmed that the Miata counter shaft is 3mm shorter than the BRZ I can put my box back together and wait on Jacks/MFactory.

Yep. There is 3mm of extra space built into the end of the BRZ/86 counter shaft on the front side, behind the end bearing that rests in the bellhousing. We had to engineer a workaround to extend the shaft we got for the first build and relocate the bearing for it to work properly in that trans.

I think the biggest expense with a 3/4/5 setup is going to be the output shaft...it is about 2ft long, incorporates two fixed gears, and likely won't be cheap to manufacture. This swap will also require another gearshaft...5th/input. So two shafts with integrated gears, and 3 separate gears (two floating, one fixed). Mike will have to chime in on how expensive this might get and you guys will need to decide if it is worth it.

So much excite, subd.

MFMike, email me whem you get a chance please.
info@949racing.con

Dear sweet Jesus, please let this work out. Subd

These are the type of things that a community can make happen if we work together rather than dispel. I knew I was not able to make it happen myself but if enough of us can work together it's a good possibility.

Out of curiosity, are there heavier than stock flywheel options for the miata?

I'm curious if they would up the death by torque level on the 6 speeds if it comes down to a peak torque spike issue.

:drama:

I refuse to bite any longer.

subd

This might be a little bit off topic but I was reading through this thread and went to the MFactory site and am I really confused or is this a 3.3 ring and pinon set for Miata diffs they list on their site for $600? Pretty sure that's less than I paid for my new 3.63 I've not got installed yet. Didn't think one of these existed. I remember a lot of talk on the MSM forum about trying to have someone make them and Bill at Miataroadster had a group buy but it fell through years ago etc. Might not be the thing for the track guys but higher HP mostly street car guys might like this.

MFactory Competition Products - Performance Driveline Components

NFW, is this real?!?

Sounds like it to me. That's just a generic pic of a front drive final and if you click on "images" they show rear drive apps too. They list the same part for the Honda F20/22C by which I think they are meaning it fits the S2000's which share the same differential as the MSM Miata which uses the same ring and pinion as the regular Miatas. Dang. Now I'm not sure if I want to go ahead with my 3.63 or check into this.......