Michael Cain

Hi Guys,

3 Questions?

What is a limited Slip Diff?

Does this effect how the car handles?

Why has Porsche not fitted a limited Slip Diff to the Porsche Cayman?

Thanks

Michael

Advevo

It s not on the cayman otherwise it would even be nicer to drive and possible be faster than a 911 on track .

Smoking up an inside wheel just looks so silly for a sports car.

Shane O'Neill

Michael
An LSD prevents wheelspin by locking up and providing drive to both driven wheels.
If you dont have one the power finds the easy option, a wheel starts spinning and just keeps spinning until you take your foot off the gas.
An LSD is not fitted to the Cayman as this would further threaten the Porsche Deity the 911.
Shane

Danton Mike

Is there and aftermarket LSD available for the Cayman/Boxster/BoxsterS lineup?

willr

It's actually very difficult to smoke the inside wheel on the Cayman if PSM is engaged. It cuts the engine back as soon as that much slip is detected. What you saw on TopGear must have been with PSM off - which is something few people in their right minds would do on the road.

BiggerTwin

Amen to that. I am always amazed at how many people turn off stability control. My friend did it in his Corvette until I pointed out that if he comes upon a large pothole or debris on the road and has to make a high speed emergency lane change he will be glad to have it on. An M3 owner admitted to having it off when he ran off the road in a fast corner and nearly flipped his car. I intend to keep it on in the Cayman S alll the time.

Alan

VicL

The 997's also do not have a LSD. The euro only sport suspension does include a LSD. Most likely the 997 Turbo will have it as well as the GT3.

I really don't understand how Top Gear got so much inside wheel spin, even with PSM off, shouldn't ABD keep the slippage in check?

BiggerTwin

Somebody who studied the tape claimed it hit some water.

Alan

willr

I reckon you could get that much wheel spin, even in the dry - just need to be very agressive with the throttle in 2nd gear.

Anyway, for Cayman owners I highly recommend SCP - it reduces the PSM interference, without completely turning it off.

frayed

Not the Turbo; it'll have open diffs front and rear. Of course the GT3 will have an LSD.

GrantG

Actually, I think the latest 996Turbos (maybe turbo S) started to offer optional LSD (don't know if it's both front & rear diffs).

To answer the question posed about adding an LSD to the Cayman aftermarket - this is difficult, since it will interfere with the PSM system. It may be possible to add a Torque Biasing Diff (like Quaife), but a real clutch-type LSD (which is what you want on the track) would certainly be a problem with PSM...

STLPCA

Grant, since I can't have both LSD and PSM for my 90% street driven, 10% non-competitive DE driven, daily driver, which do you honestly think is the better choice & why?

I've got my thoughts, but I'm always interested in hearing from (knowledgeable) others.

GrantG

Dan - These are my thoughts:

1. That 993 of yours (can't remember if you have LSD, but I think you have revised gearing) is an interesting alternative to the Cayman (there's an interesting comparison article in EVO magazine). It's worth 1/2 as much, but has almost identical objective performance, and will not depreciate NEARLY as much as a new Cayman, and has that sweet dry-sump air-cooled motor with classic looks and build quality.

2. You could buy a near-new 996 40th Anniversary edition with lowered sport suspension, LSD and PSM for much less than a new Cayman S with 50hp more power (comes with 345hp power-kit).

3. If you're set on a Cayman (and there are several legitimate reasons why one would choose one over a 993 or 996), then I guess PSM makes more sense for the majority of drivers in the majority of locales, if you had to choose between LSD and PSM. If one lived in a challenging area (mountainous for example), was a very experienced and accomplished driver (you seem to have a good bit of track experience), then I would say LSD...

I guess part of my griping is due to the fact that I know Porsche reads these boards and I think if enough people make noise, they will eventually offer -20mm sports suspension with LSD to the US option list for the 997 and Cayman. It worked for the Lotus Elise (LSD and traction control added to the options for 2006).

BiggerTwin

Dear Porsche,

Your marketing profile of the Cayman buyer is way off. There are many former 911 owners and people who thought they were going to buy a 911 waiting for their Caymans to be delivered. Most of us are older and not the young urban dance clubbers you think we are. I looked at Aston Martin but am a real driving enthusiast so I am buying your most focused driver's car. However, many of your potential Carrera buyers who are more interested in status than driving dynamics will be buying V8 Vantages. I suggest you forget about artificially limiting the power and handling of your cars for "marketing" purposes and offer the very best cars you can no matter where the engine is located.

Alan

pcar964

Want to hear something really funny? The new Honda Civic Si has LSD standard. That car costs less than $20k. Apparently, it's being marketed to a more performance-minded audience than the Cayman S. Way to go, Porsche.