Gearbox options/experiences
#281
My brain hurts!
In for results and people's thoughts though we seemed to have given up on throwing ideas around and instead of pulling the unicorn from our collective asses, we are looking to Emilio to pull one from his?
I have a semi truck and can drive it without a clutch so I feel the dog box would not be a problem to daily, but maybe I don't want to be the only one to drive my car on a long trip? At least for me, street manners matter.
I remember reading the Corky was working on a T5 conversion that wasn't suppose to weigh a ton more. Does anybody know what came of that? Even if he is slow to get it to market if that is a good option for the street car who is not looking to get every last bit out of it on the track like Sav, I will do the fab myself. Thoughts?
In for results and people's thoughts though we seemed to have given up on throwing ideas around and instead of pulling the unicorn from our collective asses, we are looking to Emilio to pull one from his?
I have a semi truck and can drive it without a clutch so I feel the dog box would not be a problem to daily, but maybe I don't want to be the only one to drive my car on a long trip? At least for me, street manners matter.
I remember reading the Corky was working on a T5 conversion that wasn't suppose to weigh a ton more. Does anybody know what came of that? Even if he is slow to get it to market if that is a good option for the street car who is not looking to get every last bit out of it on the track like Sav, I will do the fab myself. Thoughts?
What does Corky's kit cost and when will it be ready? I know it has been over a year since both he and FM separately told me they were working on this. Street manners matter to me too, but to a point. If this makes building a 400hp Miata without an ls swap make sense to me for the first time, well, I may be willing to give on some parking lot/traffic jam ease of use features. If someone is looking at this I sure hope it isn't for their only car.
I think $3k is pretty good if the solution will actually reliably take 400 of the torques, and be an easy button for installation.
#285
If anyone is interested PAR finally got back to me with a quote
"With 5th and 6th speeds sharing the same engagement hub and sleeve, both have to be either synchro or dog engagement together.
Pricing for the 1st~6th speed dog engagement gearset is $6,850 AUD( exchange rate is about .93/1 which is about $6370) which includes billet shift forks for all forward speeds.
Alternately, we can configure the gearset as a 1st~4th dog engagement/5th~6th synchromesh engagement which will work out at $5,950 AUD($5500)and include billet shift forks for 1st~4th speeds.
Shipping charges will depend on where you are located. Lead times are currently 16~18 weeks from time of order. Gear ratios can be made similar to OEM or customised to suit your vehicle/application. The only ratio which is fixed is the direct drive 5th speed which will always be 1.00:1"
"With 5th and 6th speeds sharing the same engagement hub and sleeve, both have to be either synchro or dog engagement together.
Pricing for the 1st~6th speed dog engagement gearset is $6,850 AUD( exchange rate is about .93/1 which is about $6370) which includes billet shift forks for all forward speeds.
Alternately, we can configure the gearset as a 1st~4th dog engagement/5th~6th synchromesh engagement which will work out at $5,950 AUD($5500)and include billet shift forks for 1st~4th speeds.
Shipping charges will depend on where you are located. Lead times are currently 16~18 weeks from time of order. Gear ratios can be made similar to OEM or customised to suit your vehicle/application. The only ratio which is fixed is the direct drive 5th speed which will always be 1.00:1"
#292
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The dog box discussion is very interesting, and timely for me.
Even though my Miata has a T56 in it (LS1 conversion) I am (right now) converting my transmission to a dog box setup, via faceplating of the existing gears. Long story short, after looking at several options, and keeping in mind this is for track use only, the dog box is the way to go. And, for a T56, the dog box conversion cost is completely reasonable. I am having 2nd-5th gears faceplated (the only ones I use on the track) and it will be about $2K total cost for the rebuild, including labor (I decided not to DIY this one, though I am taking care of removal/installation).
So, yes, like Emilio said, for those who have not shifted a dog box transmission on the track, they are indeed fantastic. I came out of a sport bike road racing background (5 years of club endurance racing) and one of the things I miss most is the awesomeness of how easy sport bike transmissions are to shift, FAST, under hard acceleration. AFAIK they are all dog boxes. The sequential shifting is great as well, but just having the dog gears in my track car is going to be fantastic even with the h-pattern. When I realized I could do it, I jumped on it.
For the BP (not V8) based track cars, being able to switch to a stronger dog box in a drop in transmission would be a no-brainer. I think it is fantastic Emilio is working to make this happen. Winning idea.
Even though my Miata has a T56 in it (LS1 conversion) I am (right now) converting my transmission to a dog box setup, via faceplating of the existing gears. Long story short, after looking at several options, and keeping in mind this is for track use only, the dog box is the way to go. And, for a T56, the dog box conversion cost is completely reasonable. I am having 2nd-5th gears faceplated (the only ones I use on the track) and it will be about $2K total cost for the rebuild, including labor (I decided not to DIY this one, though I am taking care of removal/installation).
So, yes, like Emilio said, for those who have not shifted a dog box transmission on the track, they are indeed fantastic. I came out of a sport bike road racing background (5 years of club endurance racing) and one of the things I miss most is the awesomeness of how easy sport bike transmissions are to shift, FAST, under hard acceleration. AFAIK they are all dog boxes. The sequential shifting is great as well, but just having the dog gears in my track car is going to be fantastic even with the h-pattern. When I realized I could do it, I jumped on it.
For the BP (not V8) based track cars, being able to switch to a stronger dog box in a drop in transmission would be a no-brainer. I think it is fantastic Emilio is working to make this happen. Winning idea.
#293
Update on the AZ-6 Dog conversion project. The engineers had already looked at the 86, S2000 and now Miata versions of the AZ-6 box and come to the same conclusion. The main and countershafts are too close to each other to get much larger gears in there. Their rough estimate is only 10-15% greater strength with a dog conversion. This is assuming a traditional modular gearset. Modular means a separate gear that slides on to the shaft. Break a gear and you just replace the gear. Assuming the OEM box is rated for 205lbs (only info I could find) we could do a modular shaft assembly and get to about 230lbs. If we go to a trick one piece shaft/gear assembly we increase strength a bit more but still not where close to 400lbs. The one piece integrated shaft gearset would require replacing the entire shaft/gearset if one tooth broke. Much more expensive to repair.
So we're looking at all options, including converting a 5 speed box to 6spd and/or dog gears. The 5 spd, I'm told, has a bunch more room for bigger, stronger gears. I'm thinking that even though the AZ-6 is rated for barely 200lbs, guys don't start shedding gear teeth until well into the 320lb range. Below that torque, it's mostly broken/worn shift forks. That being the case, I'm thinking we would be operating beyond the design limits of the proposed AZ-6 dog box but it's almost sure to last longer than what we are using now, be easier/cheaper to rebuild, have awesome ratios and dogs.
I'll update here as I learn more.
So we're looking at all options, including converting a 5 speed box to 6spd and/or dog gears. The 5 spd, I'm told, has a bunch more room for bigger, stronger gears. I'm thinking that even though the AZ-6 is rated for barely 200lbs, guys don't start shedding gear teeth until well into the 320lb range. Below that torque, it's mostly broken/worn shift forks. That being the case, I'm thinking we would be operating beyond the design limits of the proposed AZ-6 dog box but it's almost sure to last longer than what we are using now, be easier/cheaper to rebuild, have awesome ratios and dogs.
I'll update here as I learn more.
__________________
#295
I got two racers interested in the dog set if it will surface. So there are interest on this side of this pond as well.
Can someone enlighten me on how many service parts needed to make a AZ6 completely fresh, if the kit would include all gears, axles and forks?
No syncros at least.
#296
Thanks for the update Emilio.
If you forge ahead with the AZ6 it should be safe to assume some incremental improvements over the stock 6 speed. When combined with a trans cooler it should cover a lot of peoples needs. Big guns like Sav may end up needing more though. I would be thrilled with the above prospect though. With separate gears and shafts maintenance will be a breeze.
Hopefully when this project comes together I will have the cash to pull the trigger.
If you forge ahead with the AZ6 it should be safe to assume some incremental improvements over the stock 6 speed. When combined with a trans cooler it should cover a lot of peoples needs. Big guns like Sav may end up needing more though. I would be thrilled with the above prospect though. With separate gears and shafts maintenance will be a breeze.
Hopefully when this project comes together I will have the cash to pull the trigger.
#298
Update on the AZ-6 Dog conversion project. The engineers had already looked at the 86, S2000 and now Miata versions of the AZ-6 box and come to the same conclusion. The main and countershafts are too close to each other to get much larger gears in there. Their rough estimate is only 10-15% greater strength with a dog conversion. This is assuming a traditional modular gearset. Modular means a separate gear that slides on to the shaft. Break a gear and you just replace the gear. Assuming the OEM box is rated for 205lbs (only info I could find) we could do a modular shaft assembly and get to about 230lbs. If we go to a trick one piece shaft/gear assembly we increase strength a bit more but still not where close to 400lbs. The one piece integrated shaft gearset would require replacing the entire shaft/gearset if one tooth broke. Much more expensive to repair.
So we're looking at all options, including converting a 5 speed box to 6spd and/or dog gears. The 5 spd, I'm told, has a bunch more room for bigger, stronger gears. I'm thinking that even though the AZ-6 is rated for barely 200lbs, guys don't start shedding gear teeth until well into the 320lb range. Below that torque, it's mostly broken/worn shift forks. That being the case, I'm thinking we would be operating beyond the design limits of the proposed AZ-6 dog box but it's almost sure to last longer than what we are using now, be easier/cheaper to rebuild, have awesome ratios and dogs.
I'll update here as I learn more.
So we're looking at all options, including converting a 5 speed box to 6spd and/or dog gears. The 5 spd, I'm told, has a bunch more room for bigger, stronger gears. I'm thinking that even though the AZ-6 is rated for barely 200lbs, guys don't start shedding gear teeth until well into the 320lb range. Below that torque, it's mostly broken/worn shift forks. That being the case, I'm thinking we would be operating beyond the design limits of the proposed AZ-6 dog box but it's almost sure to last longer than what we are using now, be easier/cheaper to rebuild, have awesome ratios and dogs.
I'll update here as I learn more.
Bob