Differentials
miata1.6
11-26-2005, 03:18 AM
Is there a safe and rather inexpensive way to have LSD features? What is the deal with welding the diff, and would this take daily drivability away?
MagicRat
11-26-2005, 07:42 AM
Is there a safe and rather inexpensive way to have LSD features? What is the deal with welding the diff, and would this take daily drivability away?
Welding the diff (it's actually welding the spider gears on their shafts) does not give you limited slip capabilities. It locks the 2 wheels together, so they will always want to turn at the same speed.
This means the car will want to go in a straight line. Understeer in the corners becomes pronounced and severe. Tighter turns, like low-speed turns in an urban area are done in a series oh 'hops' where the inside rear wheel will wind-up then slip on the pavement. This stresses the axle shafts and gears, often leading to broken parts.
If you break an axle shaft with a welded rear end, the car will want to pull to one side instantly. at higher speed, if you are under power, this will cause an instant crash. Also, if you have a C-clip rear end (GM and smaller Ford axles) a rear wheel falls off, which is not good.
If you really want a locked rear, use a spool, instead of differential gears. But IMO a spool belongs only on the racetrack and never on the street.
For the street a LSD is always preferable, even if it costs more.
Some people have disassembled the diffs and used shims to 'preload' the spider gears against the side gears very tightly. The increased friction and binding duplicates an LSD. However, the effect does not last very long and results in damaged and useless gears.
Welding the diff (it's actually welding the spider gears on their shafts) does not give you limited slip capabilities. It locks the 2 wheels together, so they will always want to turn at the same speed.
This means the car will want to go in a straight line. Understeer in the corners becomes pronounced and severe. Tighter turns, like low-speed turns in an urban area are done in a series oh 'hops' where the inside rear wheel will wind-up then slip on the pavement. This stresses the axle shafts and gears, often leading to broken parts.
If you break an axle shaft with a welded rear end, the car will want to pull to one side instantly. at higher speed, if you are under power, this will cause an instant crash. Also, if you have a C-clip rear end (GM and smaller Ford axles) a rear wheel falls off, which is not good.
If you really want a locked rear, use a spool, instead of differential gears. But IMO a spool belongs only on the racetrack and never on the street.
For the street a LSD is always preferable, even if it costs more.
Some people have disassembled the diffs and used shims to 'preload' the spider gears against the side gears very tightly. The increased friction and binding duplicates an LSD. However, the effect does not last very long and results in damaged and useless gears.
miata1.6
11-26-2005, 10:53 AM
OK well thanks for your help. I guesse you cant really beat around the bush when it comes to that stuff.
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