https://forum.miata.net/vb/showthread.php?t=160969

Not much assumption going on there. The person working with quafie straight up said they would be stronger...

MFMike, can you make the helical teeth have more 'meat' behind each tooth or does that cause issues with the way helical gearing works? By doubling the thickness of the teeth (and so halving the number) you'd be adding more resistance to the sort of destruction bbundy is talking about. But normally a helical engages on two teeth so by widing the teeth you'd be dropping that additional contact and halving the contact area right?

Also my understanding of surface hardening is that the outer 1 or so mm of the teeth surface is hardened to prevent wear, which makes it brittle and basically non-structural. Most of the actual load goes through to the inner core that remains soft. The 1mm hardened layer on all sides means a small gear tooth has far less structure holding it to the gear than a larger tooth. So a doubling of width will actually increase strength 3 - 4 fold.

Yes, we can increase the thickness of the teeth. Normally, we don't use as high of an angle on the teeth (what we call semi-helical)

I bought parts for it rather recently. Its still available.

I can confirm from experience stronger than a stock 5 speed but not much if any stronger than the stock six speed.

The 5 speed Quaife gear set manages to get about the same strength as the 6 speed despite having much narrower gears and lighter shafts. About 12 lbs less rotating mass of shafts and gears and I believe this is the reason it feels like it shifts so much snappier than the 6 speed. The shafts are better supported by the case in the 5 speed but there is not enough room to make the gears wider face or even near as wide as the stock six speed. seems like you could make the shafts bigger maybe put some bigger bearings in but that's allot of engineering and would likely require machine work on the case. maybe you could add a spacer to the case and make it a little longer to gain some room for gear width.

The six speed probably has quite a bit of strength to gain by doing some of the tricks quaife did with the 5 speed gearset (reduced helix, lower tooth counts for bigger teeth etc) this makes it have allot more gear noise. I think it would be hard to improve on what Quaife did with for the 5 speed without digging much deeper in the bag of tricks than they did like getting bigger better bearings to fit and lengthen the box to fit wider faced gears.

If you remove those pesky synchros you can fit in much wider gears. I haven't run this yet but I'm looking forward to the whine.

https://cimg6.ibsrv.net/gimg/www.mia...5098b9583b.jpg

I am all for a dog box with Semi Helicut gears. Given the proposed cost the Quaife sequential looks like a far better value though. I am not sure I could go any other direction after getting a ride in Emilio's car anyway.

We would only be willing to make synchro engagement gearsets, not dog engagement gears.

There is far too much hassle with dog engagement, as shift ever so slightly wrong (usually not shifting fast enough) and you've broken a dog tooth, which requires either machining down the dog tooth (if there is enough of it left) or buying a whole new gear. The same actually applies to sequential transmissions as those are essentially the same but with a different shifter mechanism, although it's not as easy to shift wrong with these.

Ill try and dig up some pictures tonight of torn apart 5 and 6 speeds side by side. One thing to note however is the 5 speed has that bearing plate in the middle making for three sets of shaft bearings to the case keeping the shaft flex controlled and only 4 gears on the shaft between bearings supporting the shaft. the 6 speed has only two sets of shaft bearings and the only gear not between the bearings is 6th so including reverse there are six pars of gears on the shafts between the supporting bearings and 4th gear is right in the middle of that unsupported length of mainshaft. Shaft flex might be an issue with the six speed and probably the reason why the shafts are massively heavier in the 6 speed than they are in the 5 speed.

You know, all this makes me think I should pull open my old Leeson crashbox and take pictures - hugely beefy gears in a 5-speed case. And good ratios, and a dogleg first. Who did the gearbox you posted?

One point about helical vs straight cut gears that always seems to get left out is that straight cut gears let you move to tooth pitches and designs you can't make with helical gears - F-1 style gears take this to extremes. Saw this pointed out in an interview with an XTrac engineer somewhere - so yeah, you don't have as many teeth in engagement, but the root is hugely thicker, and that's where performance stuff fails things. Also, it's a line contact rather than basically a point contact with helical gears.

Build for the AZ-6.
Straight cut
Ratios:
2.8
2
1.52
1.22
1
.87

Isn't that just the Nismo S15 gear ratios, essentially?

I'm not 100% sure but I think it is PAR set.
MX5DS-SET ? MX5 Roadster Close Ratio Dog Engagement Gearset ? PAR ? Precision Automation Robotics

They do helical synchro sets in 5 and 6 speeds too. Might be worth finding out what power they think each box can handle.

I contacted them a few years back. By the time you get their gearset here and installed, your not too far shy of the Quaife Sequential which is rated for 375bhp. Thus why we run a Quaife sequential.
I think any higher capacity PnP Miata trans solution needs to be less than 5k installed, not including a donor Miata transmission.

I still want to see something done with Hewland FT gears, honestly, but probably have to do it myself. The annoying thing from where I sit is that all the newer options are sequential, which SCCA penalizes in most classes.

A few years ago the aussie dollar was over $1US. Now its down around 75c so there would be a 30% saving now. PAR don't have the fastest turn around time for manufacturing though.

Feb 2015 email to PAR Engineering (Precision Automation Robotics) PAR ? Precision Automation Robotics ? Precision Automation Robotics

********
1. Do you still offer the AZ-6 dog box conversion for the MX5?
We still offer the set.
2. Do you have a torque capacity rating for it? If not, could you estimate torque capacity improvement over OEM?
850N.m
3. How close can you get to the following ratios: 2.8 ,2 ,1.52, 1.22, 1, .87
Current ratio I have in stock 2.88, 1.94, 1.43, 1.15, 1.0, 0.64 (you can use you standard 6th and you will get close to 0.87 with our input shaft)
4. Total cost, FOB for such a box with your billet shift forks?
You can have this set for $7,500 Australian (USD5750 at Feb 24, 2017 exchange rate)
5. Have you produced any of the AZ-6 dog boxes for MX5 customers?
Many

Ratios are a bit wide. They no longer list any AZ-6 options on their site but I'm guessing they could still build a set to order.

That is over 600ft lbs! I wonder what my dog 5 speed is rated to. Probably 500?

If you are spending nearly $6k on a H pattern dogbox then the quaife isn't that much of a step up in price and a far better end solution given the sequential shifter.

There is a market for something in the 3.5 - 4k range. If Mfactory can produce a synchro gearset for a 6 speed for around that price that could handle 450ftlbs it would be an attractive option.

As mentioned, if we do not need to make a 1st/2nd (and thus mainshaft), the cost of a 3rd/4th/5th gear set is cost effective. Based on our previous offerings on other platforms, at the power levels you require, it would probably be around the $1500 range.

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.......

WTF the long awaited 3.3 came out and it wasnt front page news? Theres been at least 10 people at a time who wanted those for the last 6 years.

No kidding, if real and quality, will be getting a set in late July. Group buy would be automatic. These guys need to get some marketing mojo working for them.

I may be in for a group buy 3.3 if it is not Bigfoot wearing a jacket made of the skin loch ness monster with a butt plug up his made of a unicorn horn.

WOW I NEED THIS IS IT REAL.

http://miataroadster.net/gears/graph.jpg
(Pic credit to dead miataroadster threads)

MFactory Competition Products - Performance Driveline Components

Says they exist for $599. welp. Buying this next months play paycheck. Someone try it put to make sure it is not made of hopes and dreams.

Am I missing something here? Has this always been around and I am a noob ass?

NOOOOO!!!!!! I just spent all day installig a 3.63-1 set on my car 😩
https://cimg7.ibsrv.net/gimg/www.mia...6c873445d8.jpg
https://cimg9.ibsrv.net/gimg/www.mia...e6e931fcd5.jpg

Yeah, we've had it for a while now :)

any testing on "high" power (350+hp, or better yet, 300+lbft wtq) miata platforms?

Is there an update on the 6 speed gearsets, though? I can't see how a 3.3 in a high power car, aside from giving nicer shift speeds, is going to do anything but shorten the already short life of the stock 6 speed.

curious about this statement... wouldn't the rear end gearing simply move the fail point to a lower gear? We would in essence be adding a full gear (1st) with the 3.3, so it seems like a wash.

for me, the thought of an extra gear on my 4.10-5speed (3.3-6 speed is roughly equivalent through 5th gear) with extra power capacity is win.

edumacation much welcome

No you've got it. Moving the fail point to a gear that previously survived illustrates my point. Which is, numerically decreasing the rear end ration increases the torque seen by the transmission gears, and for a longer time. So the transmission, unmodified, will break earlier than before.

Well hopefully MF puts together some affordable, drop in 6 speed gear set that holds a decent amount of torque to go along with the 3.3 R&P. Then they will quietly put up for sale somewhere obscure on their website and not mention it to anyone while people scramble to buy old used 3.6s. Then they take my mom out for a nice seafood dinner and never call her again.

in the mean time, all 300+whp street car owners should be hitting the "order" button on that 3.3

Ordered my 3.3s last Thursday. That will be the ideal street R&P regardless of what tranny you use. It lets MF keep a nice close 6th gear in their gearset and it lets T5 guys run a .82 OD box instead of trying to bandaid it with a big deep .63 OD. Still haven't decided if I will put them into a Torsen and take my 3.63 hi-power OSG out, or swap the 3.63s in the OSG for the 3.308s. The $1800 race LSD in a daily driver is a little excessive but it hooks up so nice :)

Most that we've sold have been for use on the S2000

With regards to the gears, Jacks is taking this project over and will be handling it directly :)

The 3.3 would probably be nice for auto X with the 6 speeds. Makes 2nd about like 2nd on a 5 speed with the 3.9 which seems to be a popular setup. 7200 rpm gets you to 65.6 mph in second. No more bouncing of the revlimiter on every straight or having to shift to 3rd. Or if you have the power and feel like hurting yourself it should do 176.5mph in 6th.....yeah right..... They do have an open road race out here in western Nebraska. Not sure anyone runs Miatas but they are supposed to be the answer to all car questions right?

The words "limited" and "run" were haunting my dreams, so order placed.

time to start selling some miata stuff.

Been talking to Mike about the 3/4/5 gearset. I'm going to send over Miata and BRZ/86 versions of these gears so he can have a look, figure out how close they are from a manufacturing standpoint, and start getting these laid out. We have installed a Miata gearset from another manufacturer for into the BRZ/86 case with some modification, but they weren't intended to be used this way, so I am approaching the project with interchange as an intention not an afterthought.

MFactory rates their aftermarket gears at 500hp so that's the expected target. Mike says they have a stronger alloy if more capacity is required above that mark, but at a somewhat higher expense. No idea what costs will be for a set in either alloy, gotta get deeper into the planning so likely won't know for a while.

Jacks will be working in-house on development of hard anodized, billet 7075 aluminum forks for the Miata AZ6 at the request of a member here. The BRZ/86 forks are different so our existing work on that platform won't carry over (we have a 3-4 fork for that already). If I can get my engineer to focus on it I'd like to think we'll have at least a prototyped set sometime in June for test fitting.

Anyone have any ratio requests, thoughts, opinions to share? Since we are approaching this from the ground up it may be possible to tweak things a little. Keep in mind that we are only focused on 3/4/5 at this time.

If there's any wider interest in the 3.3 R&P I'll talk to Mike about pricing for a group buy.

@matthewdesigns I'd be interested on a 3.3 group buy when it happens.

Put me in on the group buy 3.3