993C4

how does PASM differ from LSD when it driving
1) normally on street and
2) at the limits on track?

can the mechanical LSD fail (ie breakdown) under normal street drving conditions?

Le Chef

The two have no connection whatsoever. PASM is an active suspension system. LSD is a mechanical traction control system (not available on 997C2S in US). Yes an LSD (like everything else in life) can fail under normal everyday conditions.

kauai_diver

Bummer Porsche doesn't offer LSD in the US., whats the reason?

BTW I wish the acronym was different, I get flashbacks when I see LSD

Ray S

Did you intend to ask about PSM vs. LSD?

gpjli2

PSM is yaw control and will manipulate throttle and brakes to prevent what it reads as loss of control within its parameters. It is standard equipment. LSD is traction control at the rear, minimizing wheel spin by shifting power between drive wheels as needed. It is optional in Europe. PASM is active suspension as indicated above. Anything that can break will.

RonCT

I've done a few searches on this a while ago and found some good information. It was my recollection that Porsche did not include LSD on the 997 because (simple terms) it wasn't needed due to the way the drive train is set up, the massive amount of grip at the rear, and PSM. I don't know that I've heard of anyone with a 997S "needing" it on street or at DE levels. If you are building a race car from your 997 then it's probably a very easy thing to add. This was my layperson recollection - I'm sure the technically adept and racer types can give more accuracy and detail.

TT Gasman

Yet you can order LSD on a turbo, go figure. Porsche should have offered -20 and LSD as an option.

Mark in Baltimore

If you drive hard enough at a DE, you will need LSD, especially for stability under heavy braking.

tstafford

It is interesting to me that it is offered on the TT. I'm not a mechanical engineer, but it would seem less necessary in an AWD car.

Moderato

I would think that LSD would just come standard on the TT, like it does on the GT3. Is there any reason that someone with a TT wouldn't want to have an LSD?