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Another Transmission Option?

 
Old 01-10-2019, 10:18 AM
  #41  
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Originally Posted by rrjwilson View Post
Is it sonofthehill that is continually breaking 4th on track?
I remember a thread talking about getting hardened gearsets where someone came in and pictured a few of the several gearboxes he/she had ruined.
I specifically remember though that at his/her power level you didn't need to change into it badly it just went at the torque level he had.
If this wasn't sonofthehill whoever it was would be a perfect candidate also.
As someone keenly interested in this topic and home-brewing strengthening options, Ive been searching fruitlessly for pics of internals from failed 5sp boxes. Would love to see some.
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Old 01-10-2019, 10:24 AM
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Originally Posted by themonkeyman View Post
As someone keenly interested in this topic and home-brewing strengthening options, Ive been searching fruitlessly for pics of internals from failed 5sp boxes. Would love to see some.
I'll see what I can do, and link back here if i can put something together
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Old 01-10-2019, 11:39 AM
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No, I have never broken 4th in any of my 5 speeds. I have not broken any at the track yet either, always on the street, in 2nd, 3rd and 5th.

Here is my most recent carnage, I didn't open this one but this is definitely an input shaft tooth, matched it to a different one. I did manage to keep the input shaft from moving forward and sheered the whole tooth(I think), I had only sheered approximately 90% of the teeth previously.

I will email them today, I have an unusually busy day though.



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Old 01-10-2019, 12:38 PM
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Technically, you can reduce the likelihood of breaking an input shaft tooth by 50% simply by removing every other tooth.
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Old 01-10-2019, 12:56 PM
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I see no fault in that logic
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Old 01-10-2019, 07:23 PM
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Except that even with only one tooth removed, the car becomes almost completely undrivable.
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Old 02-14-2019, 07:11 PM
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Update for AZ6 users:

Contacted Walter Motorsports. Asked if they were working on anything for the AZ6. They said it was on their to do list but they are busy with 5spd stuff for SCCA racers. They weren't aware of the market for a beefier AZ6 so I shared some
info and stats. They're interested so we're sending them a few boxes to evaluate and inspect.

If anyone reading this has a complete AZ6 with sheared gear teeth, LMK. We need one for science.
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Old 02-15-2019, 03:59 AM
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Originally Posted by emilio700 View Post
Update for AZ6 users:


If anyone reading this has a complete AZ6 with sheared gear teeth, LMK. We need one for science.
IIRC bbundy has about a dozen

--Ian
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Old 02-15-2019, 11:31 AM
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Originally Posted by codrus View Post
IIRC bbundy has about a dozen

--Ian
Sent him an email a week or so ago, no reply yet. Maybe I'll give him a call
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Old 02-18-2019, 12:59 PM
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Semi-unrelated: I dream of a 6 speed box that is a direct fit, can take 400+hp and cruise at 70mph around 3k rpms. Basically I'd like a beefed up factory 6 speed with a bit of a change to the gear ratios.

I don't need a box that strong and maybe I never will, but I say if you're gonna dream... Dream big.
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Old 02-18-2019, 01:56 PM
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Originally Posted by 90LowNSlo View Post
Semi-unrelated: I dream of a 6 speed box that is a direct fit, can take 400+hp and cruise at 70mph around 3k rpms. Basically I'd like a beefed up factory 6 speed with a bit of a change to the gear ratios.

I don't need a box that strong and maybe I never will, but I say if you're gonna dream... Dream big.
Hmm. That is what I have with the BMW 6 speed now. Some assembly required but it isn't bad. Just bolts in.
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Old 02-18-2019, 07:32 PM
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I emailed with them a few weeks ago. They said their biggest problem was being too busy and it's a 2 man operation. Hopefully I will hear from them soon, as I keep seeing good deals on getrag 260's locally.

More input shaft carnage for your viewing pleasure.


This is why I can't seem to run full power in any gear but 4th. This gear transmits power to the rest of the gears. It would be nice to have a Miata transmission in the long run, that way I don't have to figure out a neutral safety switch and speedo.
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Old 02-18-2019, 08:01 PM
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I wonder if the cryogenic treatment would add strength to this piece. I'v read a lot of serious people who swear by it, but also race with a friend who is a metallurgist for Ford Motors, who says they had tested it years ago, and no benefit; said if it worked, they'd be using it. If it does work, this is exactly the kind of parts I'd want to treat.
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Old 02-19-2019, 06:17 AM
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Originally Posted by tomrev View Post
I wonder if the cryogenic treatment would add strength to this piece. I'v read a lot of serious people who swear by it, but also race with a friend who is a metallurgist for Ford Motors, who says they had tested it years ago, and no benefit; said if it worked, they'd be using it. If it does work, this is exactly the kind of parts I'd want to treat.
It's not that it doesn't work. Cryo treatment makes some difference but "cryo cycling" with multiple slow cycles yields a great benefit. But it takes time (almost a week) and money Ford probably didn't value. I've seen everything from cutting tools used to make eyeglasses to fleet vehicle brakes tested and the differences in life were substantial. Last time I was at the facility it was expanding because of increased volume of orders.
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Old 02-19-2019, 12:58 PM
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Originally Posted by 90LowNSlo View Post
Semi-unrelated: I dream of a 6 speed box that is a direct fit, can take 400+hp and cruise at 70mph around 3k rpms. Basically I'd like a beefed up factory 6 speed with a bit of a change to the gear ratios.

I don't need a box that strong and maybe I never will, but I say if you're gonna dream... Dream big.
If they can beef up the overall trans, use a S15 (or FT86) 6th gear set (assuming it'd fit), and put in a 3.63 and you're there.
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Old 02-19-2019, 01:16 PM
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Originally Posted by sonofthehill View Post
More input shaft carnage for your viewing pleasure.
This is why I can't seem to run full power in any gear but 4th. This gear transmits power to the rest of the gears.
Do you have a complete, intact AZ6 with broken gears (other than input shaft) you can donate? Email us if you do [email protected]
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Old 02-19-2019, 02:41 PM
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Originally Posted by emilio700 View Post
Do you have a complete, intact AZ6 with broken gears (other than input shaft) you can donate? Email us if you do [email protected]
Pretty sure sonofthehill runs 5-speed only.

1993z32 might be able to donate to the cause?
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Old 02-19-2019, 02:59 PM
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Originally Posted by sixshooter View Post
It's not that it doesn't work. Cryo treatment makes some difference but "cryo cycling" with multiple slow cycles yields a great benefit. But it takes time (almost a week) and money Ford probably didn't value. I've seen everything from cutting tools used to make eyeglasses to fleet vehicle brakes tested and the differences in life were substantial. Last time I was at the facility it was expanding because of increased volume of orders.
Thanks Sixshooter; I'v been trying to reconcile what my buddy had told me, with the **** load of knowledgable racer's who treat everything they can get off their car. Glad to be brought up to speed on this!
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Old 02-19-2019, 03:15 PM
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I don't have any of my boxes left.

Side note, if anyone is planning on beefing up the 6-speed in any way, the synchro rings, especially 4th, need to be welded to the gears. Due to the direction of the helical cut the ring separates from the gear (they are press fit) and the trans proceeds to attempt to go into 3rd and 4th at the same time. This was the only reason I lost 2 6-speeds at 350wtq, no broken teeth or anything else. (And this happened within a few pulls). Note that I was using an unsprung twin disc, some people attribute the failures to the aggressiveness of the clutch, but it's a weak point regardless.

Pictures and more in depth description of failures:

https://www.thecarpassionchannel.com/trans-fail

Originally Posted by cpierr03 View Post
Pretty sure sonofthehill runs 5-speed only.

1993z32 might be able to donate to the cause?
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Old 02-19-2019, 07:30 PM
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Sorry Emilio, I only have 5 speed boxes. All of my 5 speeds have sheared teeth on the input shaft in a similar manner. This could seem like a failure in 1st, 2nd, 3rd, or 5th, but it was always the input shaft in my case. I was going to scrap the 2 complete junk boxes I have, but those guys suggested they might still have some core value.

As I understand cryo treatment it helps more with wear characteristics than with tensile strength, not sure what the solution is.

Greg, didn't you bury those 6 speeds in your yard or something, can't you dig one up
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