[Liquidpaper]

My track weekend is over and I have been able to (at least a little) assess the difference that an LSD makes in an M235i on the track compared to stock.

In a word -- huge.

(Just a reminder, the differential is custom with 35/60 ramps, about 90(ish) pounds of preload, and a 3.46 ratio.)

It's honestly like driving a different car, for the better. Every corner is confidence inspiring (unless you blow the turn). You're never really afraid of losing your tail. It's very hard to upset the car with the differential in. In some limited circumstances (when you blow a turn and try to correct), you feel the back step out a little, but it is so progressive and predictable that it feels like the chassis is feeding the movement into your brain telepathically. You just kind of go "oh . . . . back's going out . . . okay, fixed" and you're good to go.

I've never driven an "M" car, but I suspect that this is what some people refer to when they mean that the car feels more "connected" to the road. At all times this weekend I felt 1. stable and 2. confident. It's really pretty amazing.

Comparing this weekend to the previous dozen or so days I've had on track with an open differential, I understand what all the fuss is about (at least for track applications). It's just a totally different experience.

As far as handling characteristics, I cant really tell if my car is tight or loose right now. Sometimes it feels tight, but I keep turning the wheel and the car keeps turning in, so I'm not plowing in too hard. On the other hand, I've had a few minor situations when my tail got loose, but they were extremely controllable and not frightening. I suppose my car is just about neutral? I think I need some more seat time to figure it out.

As far as the street . . . I'm not convinced it's worth the several thousand dollar (at least 2.5k for the M Performance diff) premium. Yeah, you do feel it, but if you're driving like a sane human being, it's kind of rare. I suppose it makes you feel more like this is a true performance car with the limited slip carrier, but you honestly don't need it. It's just nice to have. On the track however, if you plan to do it often, this is a very important upgrade.

Also, the shortened ratio (3.46) is pretty cool. That extra torque is crazy -- very useful and fun on both the track and the street. I think it fits the car's personality a little better than the 3.08 (revs faster), but I can understand why BMW went with the 3.08 (fuel econ and all). It's really a personal preference thing, but holy shit does this car launch now.

I'll post the video after I am done editing. I was running in the low 2:20's pretty consistently driving at about 7/10ths (around 2:22). I'd never been to this track before, so it was a learning weekend. Tons of fun though, especially turn 13 -- heavily banked, so you can pull some serious g's going through it. Would recommend going to this track (if you're West Coast).

EDIT: No video this time. Camera is shaking too much (for some odd reason) and the audio is terrible (tried a different setup this time -- too much wind noise).