50/80 or 40/60 LSD?

[930LDR]

Looking into a Guard LSD for the 930. Principally use the car on the track but I do often drive it on the street to the track and occasionally on the weekends as well. From what I hear the 50/80 is really the optimal track setting but I am concerned that it will be too difficult to deal with for the occasional street drive. Anyone have any relavent experience? thanks

[Lukesportsman]

I certainly don't recommend it, nor is it good for the car's mechanicals, but I've driven my car with a spool in it on the street before. Sure she understeers like a pickup truck, but in the dry it certainly hasn't provided a "threatening" or unsafe situation. NO, I wouldn't have lent the keys to my wife or mother, but then again.....that wasn't the only characteristic of the car that might have prevented that.

So, no its not optimal and may require some backing off to 8/10 rather than 9/10's in corners, but if used mostly for track I'd set it up mostly for track and make the sacrifice on the street. Just my thoughts.

[spuggy]

I think Luke has it exactly right. Set it up for where it's going to mostly be, and put up with it elsewhere.

My 40/65 feels great on the street. Which means you'd probably be able to do much better for dedicated track use.

Face it; "drive it to and from the track and sometimes at weekends" is pretty much dedicated track use.

[pdqcarrera]

Have you considered the torque biasing version?

[930LDR]

Torque biasing units are better set up for autox cars. Prevents some of the lower speed understeer but doesn't provide any of the decel stability that the LSD brings to the party.

[pdqcarrera]

Originally Posted by 930LDR

Torque biasing units are better set up for autox cars. Prevents some of the lower speed understeer but doesn't provide any of the decel stability that the LSD brings to the party.

Here we go again... LOL... ;-)

How important deceleration stability is versus all the other advantages the TB offers isn't necessarily a slam dunk for the LSD even for a 100% track car.

FWIW - a properly setup/well balanced 911 can trail brake quite nicely with a TB diff. I've been racing with both and while the 2 shop cars I race are LSD my own is a TB and that's my preferred choice for most of the tracks we race on here on the left coast.

[kellcats521]

Originally Posted by pdqcarrera

Here we go again... LOL... ;-)

How important deceleration stability is versus all the other advantages the TB offers isn't necessarily a slam dunk for the LSD even for a 100% track car.

FWIW - a properly setup/well balanced 911 can trail brake quite nicely with a TB diff. I've been racing with both and while the 2 shop cars I race are LSD my own is a TB and that's my preferred choice for most of the tracks we race on here on the left coast.

Agreed. The worm gear (TB) differential was adapted to cars for open track (NOT A/C) use.

[930LDR]

Simply basing my comment on what I am being told by those that know more than I do on the matter. I am sure that there are people who use TBs and are quite happy with them on the track.