Differentials.
#1
DEI liberal femininity
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Differentials.
I was looking at the diff picture loki posted in the oil pump thread and wondering if all pinion gears are supported only at one point.
Here's one like he posted:
It's got that extra bit of shaft sticking out the gear-end. is that supposed to go into a second bearing? The picture below suggests that may be the case. I can only imagine it makes the whole setup much less prone to flex and mis-meshing of the gears which is a pretty frequent reason gears fail.
sorry, that's huge.
Discuss!
Here's one like he posted:
It's got that extra bit of shaft sticking out the gear-end. is that supposed to go into a second bearing? The picture below suggests that may be the case. I can only imagine it makes the whole setup much less prone to flex and mis-meshing of the gears which is a pretty frequent reason gears fail.
sorry, that's huge.
Discuss!
#7
Why does the Ford 8" have to be a boat anchor? You can get them with aluminum casings, first off...secondly, presumably you're adding weight to the front-end of your car with a V8 conversion, are you not?...would you not want to help balance this by adding a little weight in the rear, where you'll already be starved for traction?
#10
If a bearing up top will keep it from flexing i don't see any reason why it wouldn't be better. I don't see how we could to that to a miata differential though.
I haven't had a miata differential apart yet, the ones I have had apart have two bearings. One that is pressed onto the gear itself and another in the case. So the shaft is already supported by two bearings over the length of the main shaft.
Is this the case with the miata diff?
I haven't had a miata differential apart yet, the ones I have had apart have two bearings. One that is pressed onto the gear itself and another in the case. So the shaft is already supported by two bearings over the length of the main shaft.
Is this the case with the miata diff?
#11
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Yes, two bearing are better. Does that mean we need to add a second one at each wheel? What about a turbo? How about one at each end, and another in the middle?
Sheesh, it's basic engineering.* If you can get away with one that will do the job, you use one. If you need two, you figure out how to put one in. Simply put, the design is adequate for the loads anticipated. You double or tripple the HP and torque, you get failures. It wasn't designed for that. Cost is the major driving factor in automotive design, and bearings (and the machining needed to support) them ain't cheap.
*Yes, I'm a mechanical design engineer.
Sheesh, it's basic engineering.* If you can get away with one that will do the job, you use one. If you need two, you figure out how to put one in. Simply put, the design is adequate for the loads anticipated. You double or tripple the HP and torque, you get failures. It wasn't designed for that. Cost is the major driving factor in automotive design, and bearings (and the machining needed to support) them ain't cheap.
*Yes, I'm a mechanical design engineer.
#13
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Yes, two bearing are better. Does that mean we need to add a second one at each wheel? What about a turbo? How about one at each end, and another in the middle?
Sheesh, it's basic engineering.* If you can get away with one that will do the job, you use one. If you need two, you figure out how to put one in. Simply put, the design is adequate for the loads anticipated. You double or tripple the HP and torque, you get failures. It wasn't designed for that. Cost is the major driving factor in automotive design, and bearings (and the machining needed to support) them ain't cheap.
*Yes, I'm a mechanical design engineer.
Sheesh, it's basic engineering.* If you can get away with one that will do the job, you use one. If you need two, you figure out how to put one in. Simply put, the design is adequate for the loads anticipated. You double or tripple the HP and torque, you get failures. It wasn't designed for that. Cost is the major driving factor in automotive design, and bearings (and the machining needed to support) them ain't cheap.
*Yes, I'm a mechanical design engineer.
OK so my point was to analyze the potential failure modes of the tranny. if at triple the hp we flex the pinion away from the ring gear, it's going to fail. what can be done to mitigate it? is replacing it with a same-type setup going to also fail later?
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who isn't a mechanical engineer. cal poly slo '98.
OK so my point was to analyze the potential failure modes of the tranny. if at triple the hp we flex the pinion away from the ring gear, it's going to fail. what can be done to mitigate it? is replacing it with a same-type setup going to also fail later?
OK so my point was to analyze the potential failure modes of the tranny. if at triple the hp we flex the pinion away from the ring gear, it's going to fail. what can be done to mitigate it? is replacing it with a same-type setup going to also fail later?
Sounds like it might work, if you had the time and patience to work it all out. Fab up a stamped bracket, press in a bearing, and either grind a race on the end of a pinion (expensive), or drill the end and insert a pin to ride in the bearing. Then, of course, you have to drill and tap holes for mounting that bracket, all while avoiding clearance issues. Possible grinding/milling of the bearing caps for flats to provide a mounting surface.
I'm guessing the bracket would have to be 1/8" or thicker to be strong enough, and about 1" or more wide, depending on the bearing used. Is there room for that in a torsen diff?
All in all, considering the machining involved, it goes a little beyond the standard DIY project. Not many people have direct access to machine tools, so it would have to be done on a 1 to 1 basis. Possibly an exchange; send in a core, or pay a lot more. Not sure it's all worth it, when you can just get another diff.
#20
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something like that would be awesome. but yeah, probably beyond the scope of DIY. great if you could find some shmuck to produce complete diffs with the ratio you want and the LSD you want. I dont want a torsen, I like my kaaz.
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