Quote:
Originally Posted by 10"
Quote:
Originally Posted by T1M
My main issue with the 1M is the unpredictable VLSD. It is not a normal plated clutch type LSD and it's ability to lock depends on the viscous section first shearing a fluid by differential wheel speeds across the rear axle. This causes the fluid to expand and force a piston against the plates, locking the diff. However once locked, the fluid contracts and the diff unlocks, then a wheel speed difference again must exist to re-lock the diff.
This locking/unlocking characteristic being based purely on wheel speed difference is appropriate for traction on variable friction surfaces like patches of snow or ice but is unpredictable and inconsistent when driving spiritedly. Usually a plated LSD works by locking more or less based on torque applied to the diff, either acceleration (1-way) or deceleration (1.5-way or a more aggressive 2-way).
To me, despite the analogue feel and design of the 1M, the unpredictable diff is a very poor match for a short wheelbase car with a high-torque 3L turbo engine. It makes it a fun ride/wild/angry car but in actual performance/handling terms it's lacking vs the newer BMW M's using the new active LSD's.
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Quote:
Originally Posted by T1M
My main issue with the 1M is the unpredictable VLSD. It is not a normal plated clutch type LSD and it's ability to lock depends on the viscous section first shearing a fluid by differential wheel speeds across the rear axle. This causes the fluid to expand and force a piston against the plates, locking the diff. However once locked, the fluid contracts and the diff unlocks, then a wheel speed difference again must exist to re-lock the diff.
This locking/unlocking characteristic being based purely on wheel speed difference is appropriate for traction on variable friction surfaces like patches of snow or ice but is unpredictable and inconsistent when driving spiritedly. Usually a plated LSD works by locking more or less based on torque applied to the diff, either acceleration (1-way) or deceleration (1.5-way or a more aggressive 2-way).
To me, despite the analogue feel and design of the 1M, the unpredictable diff is a very poor match for a short wheelbase car with a high-torque 3L turbo engine. It makes it a fun ride/wild/angry car but in actual performance/handling terms it's lacking vs the newer BMW M's using the new active LSD's.
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What you've described as a possible weakness is exactly what some of us want!!  things like this are exactly one of the reasons why the 1M is such an engaging car to drive. If people are after the "latest tech" then it's not the car for them. If they're after a classic driving experience closer to older M cars then it's absolutely for them... |
I have to agree. The diff has its issues but overall it makes the car cool and engaging to drive. Maybe it's just me. When I was 15 I went stayed at a horse Ranch for a week. I was a city kid and learned to ride a horse. They put me on the most docile horses they had. It was nice for a couple of days but they had a Mustang that was huge and awesome looking. He would snort and headbutt other horses. He would periodically stand on his hind legs and the cowboy would have to calm him down. I kept asking if I could ride him and they told me no until the last day. Finally I climbed on top of the beast. It took way more skill and effort to keep him going but when he galloped it was scary and fast. I was a little scared the whole time. Finally we made it back to the ranch safe and sound and I was so excited I got off too fast and my boot got caught in the stirrup. The horse moved and knowing a friend was dragged to death like this a year before I panicked and kicked the horse in the side to push away. The horse kicked me and when I was in the ground tried to stomp me. I rolled into a ditch and the cowboys saved me. I never rode a horse again but I don't remember any of the docile horses I rode all week. I only remember riding that wild mustang now 35 years later!
So if you're into smooth and docile that's ok but sometimes the most memorable rides are a little wild and a little scary. The world is full of OSHA approved comfy rides. Some of us appreciate something a little different.