michaelp

Autocrossed my base C2 a couple times. No track time yet, next month. It's a great handler. Finding the limits of traction is really challenging. I've been able to get the rear end out some with normal PSM (in sports plus) -- need to try PSM Sport next time. Are you looking to aggressively track or AutoX your car? How experienced are you with performance driving? My take is the base is more than adequate.. but if you plan to regularly run your car hard and obsess over times, would consider the S or GTS. Just make sure to spec the sports chrono!

Outlaw 06

It's troublesome that Porsche doesn’t feel the need to put LSDs in all of their sports cars as standard equipment. My son’s $25k 2020 Honda Civic Si came stock with a helical LSD, for crying out loud!

michaelp

Agreed. As far as I've been able to ascertain Porsche does not publish what kind of diff is in the base C2. It's apparently part of the PDK transmission. Someone needs to get in there and get a closer look.

Newport IRL

It is odd that there isn’t some technical info from Porsche. I have a base and it drives like it has a LSD on the street for all practical sense. The PDK and PSM effectively prevent the one wheel peel that you’d expect with an open differential.

BlueFog

In older cars without any traction control a limited slip made a big difference particularly on a shorter and twisty circuit.

I am sure there is still a benefit in having an LSD in a modern Porsche but less so with all the electronic traction controls and would only really see the difference on a circuit.

On public roads I certainly am not going at a speed or driving in a style that it is needed. If I was I would lose my licence very quickly.

Under hard acceleration from a standstill I sometimes sense some movement in the back end, only very slight, but I had the same sensation in an s.

I went on the Porsche handling circuit at Silverstone and pushed a base hard and in the areas I thought it would lose traction (corkscrew) it was fine and no issues under braking. Of course an s would go faster but mainly due to the increase performance mid range in third gear upwards

Would I prefer an LSD - yes, do I miss not having one - no.

SBAD

Why would you need LSD with all-wheel drive?

Tobeit

What do you mean no technical info? Porsche is pretty clear that only the S and up come with LSD but not the Base. I agree with what was said earlier why a $100k sports car comes w/o it but I guess they figured for 99% of the customers and how they drive they will never recognize it has none - including myself.

michaelp

There is no technical info on what kind of diff is in the Base C2. Yes they clearly state what’s in the other models, it’s even an option on the C4 Base, but no details on what kind of diff is in the Base C2.

ohniner

it was my understanding that Porsche uses an electronic LSD in the base Carrera, not an actual device but utilizes the abs and possibly the engine management to control wheel spin vs an actual device (clutch pack) in the differential.

drcollie

Because your rear end is still open, only one wheel turns. AWD is really "Two-Wheel Drive", with one wheel pulling on the front, one on the rear. You are not getting power down to all fours, the power goes to the wheel on each end that has the most traction. For max performance you want Limited Slip in the rear as a 911 is still a rear-engine car, rear wheel drive biased as well. That in effect gives you Three Wheel Drive.

If you get into the world of off-roading, you will see what are called "Lockers", for both the front and rear diffs, where you press a button and it locks the front diff and rear diff for true All Wheel Drive where all four wheels are supplying power. Useful in mud and big rocks. The don't turn very well when engaged though!

Outlaw 06

I currently have LSDs in all my cars (they all have manual gearboxes and rear-wheel drive too). I have clutch-type, LSDs in my 2021 Porsche 718 Spyder, my 2004 BMW E46 M3 coupe and my 2021 BMW M240i coupe (dealer-installed option). I have a helical LSD in my 2003 NB MX-5 Miata race car. I’m used to driving cars with LSDs, so I might have a better feel for the shortcomings of cars without LSDs compared to people who only drive open differential cars.

When both drive wheels are on the ground, I can’t perceive any difference between helical and clutch-type LSDs. However, whenever I find myself in a situation where one of the drive wheels momentarily lifts off the ground (perhaps when taking too much curbing on a track), the helical LSD’s power delivery/traction is less predictable and inferior to a clutch-type LSD. That’s the only (slight) performance con of helical LSDs in my experience. Both types of LSDs provide impressive performance over open differentials though.

Regarding my M240i that came standard with an open differential. I drove it with both the open differential and with an LSD, so I experienced the differences in the same car. This car has a Dinan tune and cold air intake, so it’s outputting nearly 400 hp and 400 lb-ft of torque now. The first thing I do after starting my car is toggle the Driving Dynamic Control switch to “Sport +” mode, to negate the electronic nannies. The dealer-installed M-Performance LSD greatly improved the power delivery to the rear wheels on the staggered, 18” Michelin Pilot Super Sport max performance summer tires, in wet and dry conditions. The car’s handling and traction with the LSD are now predictable and far superior to the way it was with the abysmal stock open differential. It’s literally a night and day difference during both acceleration and throttle lifts or braking (decelerating) for turn-in. The adverse yaw that was induced by the car’s stock open differential under hard acceleration has also been eliminated by the LSD. The car’s electronic nannies are also significantly less intrusive with the LSD (specifically, the computer-induced engine power reduction and intermittent braking action on the slipping wheels that the car routinely exhibited with the stock open differential).

"Positraction" LSDs have been around in various forms for over 60 years, and it astounds me that Porsche doesn't even offer it as an option in all their sports cars with engines producing well over 300 hp and 300 lb-ft of torque. It just indicates that Porsche isn't serious about the performance of these cars. ESPECIALLY when considering that Honda puts helical LSDs as standard equipment in $25k Civic SIs (as I mentioned previously).

I realize this post was slightly off-topic, but it's my experience/opinion with LSDs and open differentials.

michaelp

Thanks for sharing, but there's no information from Porsche that there is an open diff in the base 992. They literally do not state what is in there. Speculation is that it's some kind of electronically controlled diff, possibly even an LSD.

Next time I'm on the AutoX course I'll run in the car in the various PSM modes, see how it behaves. At the last event I ran in Normal-PSM mode, and had zero inside wheel traction issues.

aggie57

No, it has traction control but not an LSD. Two different things.

Tompoodie

Michaelp...that would be wonderful to write up your experiment in this thread...would be very valuable info.

I wonder if a company like M-engineering could program LSD into the PDK software?

Tompoodie

You are right. With open differential the power goes to the wheel with less traction and 1 wheel will spin.
I agree while it is fun and challenging to slide the rear with LSD, another way of looking at it is a on a tight, curvy road if you lose traction with an open differential 1 wheel will spin and the rear end will not move sideways, potentially into oncoming traffic.