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Discussion Starter · #21 ·
Hood Automotive tire Automotive design Motor vehicle Bumper

Automotive tire Hood Motor vehicle Car Automotive design

Weekend highlights: 1. Discovered the current meter provided with the Orion bms bolts right up to where the factory current meter was on the battery pack bulkhead.

2.Scored some Smart Car seats!
 

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For the diff you can do what broke drifters do, make a Lincoln Locker by welding the spider gears to each other. Idk how much a Tesla diff sells for or if more valuable to you on the shelf for possible future use in stock form though.
 

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Discussion Starter · #29 ·

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Discussion Starter · #30 ·
For the diff you can do what broke drifters do, make a Lincoln Locker by welding the spider gears to each other. Idk how much a Tesla diff sells for or if more valuable to you on the shelf for possible future use in stock form though.
Thanks! I’m very torn on this topic between a locker or a lsd. In a perfect world I would want a system where I could switch between some sort of locked center diff (for 4wd mode) and having only the rear wheels fully locked (for 2wd for driving around town). My friend mentioned something like a drivetrain decoupler used on vw vans. As awesome as that’d be eventually—I think I’ll start with either an lsd or a machined spool. The model 3 lsd’s do seem to cost quite a bit of money and machining a spool could cost even more. Luckily , my father is a machinist and offered to make me one if I decide to go that route (and If there’s not a commercially available one at that time).
 

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For off-road you’d ideally want a spool. A locking type (Detroit locker) differential would be the next best choice followed by clutch type. Idk how serious of an off-road machine you plan this to be but I’d be a little concerned about long term wear with a viscous or quaife type differential especially with the front shaft removed or hubs not locked in. This would mean no load on the “front” side of the diff and it would be constantly working to send power to the rear and not unload.
A spool and decoupler would be ideal, and not terribly complicated to cobble together. I’ve seen some done with splined shafts, matching coupler and some bearings. There will be added length to the Tesla drive unit and the need for shorter driveshaft(s) though.
If your machinist father can cut the required splines for a spool you may want to look into having him make a mini spool instead of a full spool. A mini spool simply replaces the spider gears in the differential with interlocking blocks to make it a spool. Less material, less material removal, less demanding tolerances, don’t have to change how the diff is shimmed in the housing, no permanent change to the existing diff.
 

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Idk how serious of an off-road machine you plan this to be but I’d be a little concerned about long term wear with a viscous or quaife type differential especially with the front shaft removed or hubs not locked in. This would mean no load on the “front” side of the diff and it would be constantly working to send power to the rear and not unload.
A spool and decoupler would be ideal, and not terribly complicated to cobble together. I’ve seen some done with splined shafts, matching coupler and some bearings. There will be added length to the Tesla drive unit and the need for shorter driveshaft(s) though.
If your machinist father can cut the required splines for a spool you may want to look into having him make a mini spool instead of a full spool. A mini spool simply replaces the spider gears in the differential with interlocking blocks to make it a spool. Less material, less material removal, less demanding tolerances, don’t have to change how the diff is shimmed in the housing, no permanent change to the existing diff.
With nothing connected to the front, most LSDs including the Quaife ATB or any Torsen wouldn't drive the vehicle at all, because they have a limited torque biasing ratio - they can apply more torque to the slower-turning output, but only to a limited multiple of the torque to the faster-turning shaft.

If your machinist father can cut the required splines for a spool you may want to look into having him make a mini spool instead of a full spool. A mini spool simply replaces the spider gears in the differential with interlocking blocks to make it a spool. Less material, less material removal, less demanding tolerances, don’t have to change how the diff is shimmed in the housing, no permanent change to the existing diff.
A full spool is not a permanent change, either - the complete original diff is removed and replaced with the spool, and that is reversible. Only welding or otherwise mangling the pinion and side gears is permanent.
 

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For off-road you’d ideally want a spool. A locking type (Detroit locker) differential would be the next best choice followed by clutch type.
I think ideal is a differential (preferably limited-slip, but even open) with a locking device and a disconnect. That allows the same operating modes as a spool plus disconnect, but adds four wheel drive with a differential. Yes, its complex, adding both a front axle disconnect and a differential lock to the basic transaxle or transfer case; it's also a production item as a transfer case.
 

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A full spool is not a permanent change, either - the complete original diff is removed and replaced with the spool, and that is reversible. Only welding or otherwise mangling the pinion and side gears is permanent.
But creating a full spool from scratch, I believe, would be more expensive. I then listed the reasons why I believe creating a mini spool vs creating a full spool would be advantageous and more likely for his father to agree to making. No harm in giving people ideas/options
 

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I think ideal is a differential (preferably limited-slip, but even open) with a locking device and a disconnect. That allows the same operating modes as a spool plus disconnect, but adds four wheel drive with a differential. Yes, its complex, adding both a front axle disconnect and a differential lock to the basic transaxle or transfer case; it's also a production item as a transfer case.
Ideal is going to vary by person, vehicle, terrain, etc. A center differential (open or lsd) that’s not locked can help “turn in” ability at speed, great for rally cars but not likely to be felt in a leaf spring front suspension jeep. More likely is typical jeep driving that is slower, over obstacles, where a tire may end up hanging in the air occasionally. If the jeep in question doesn’t have a lsd or locker in the axle where the tire is hanging in air, only a locked center diff or spool is going to keep the jeep moving. The tire doesn’t even have to be in the air, could be in looser sand than the rest, just a position where less weight/contact with the ground is made than the others and the jeep is stuck. As you mentioned the available Quaife atb wouldn’t help this situation with a tire in the air, maybe a little in others where the difference in traction between the tires isn’t as great. So the owner needs to decide what will suit his needs. But for typical jeep driving the differential options are, weld the differential gears to create a spool, have his father make a custom mini spool or custom full spool, put lockers in the front and rear axles and run the quaife as 4wd all the time or find a company willing to make a different style of lsd/locker for the Tesla drive unit.
 

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But creating a full spool from scratch, I believe, would be more expensive. I then listed the reasons why I believe creating a mini spool vs creating a full spool would be advantageous and more likely for his father to agree to making. No harm in giving people ideas/options
I agree. I was just correcting the idea that a full spool would involve irreversible changes; it wouldn't any more than a mini spool would.
 
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