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Does the 718 Cayman GT4 mechanical LSD just drop into a regular 718 S?

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8.7K views 12 replies 8 participants last post by  Gil718s  
#1 ·
Hey all, new to the forum and just got a new-to-me 2017 718 Cayman S that unfortunately is not optioned with PTV. I do plan on doing some HPDEs with my 982 and got a lead on affordable GT4 LSDs that were swapped out for race diffs on a fleet of GT4s. The seller claims that they drop right in and work but is that true? Any drivetrain experts know?
 
#2 ·
Welp, it’s less than $800 I guess I’ll be a guinea pig. Here’s the listing on eBay if anyone else is interested. I think they have 8 more.

 
#3 ·
It lists all the 718 manual models and I looked at that myself. It isn't a must have for me, but as I get better on the track, it would probably be helpful. I'm anxious to hear your experience. Only 6 left at this moment.
 
#4 · (Edited)
I won’t be installing it immediately as I want to get some familiarity with my 718 S first (freshly bought and still at a NJ dealership waiting to be shipped to me in Texas) and do at least one track day as a baseline before I start modding. I’ll gladly report back with my impressions when the LSD is in.
 
#8 ·
I spoke to the eBay vendor. The 981 & 982 share the same gearbox. I asked what vehicles the 2 individuals whom purchased the diff had and he did not know. We need some one with first hand experience. The process for installing the diff won't be as simple as a bolt on or inexpensive for that matter. I'm also questioning the actual necessity considering the car has so much grip as it is. Aside from the benefits in inclement weather (which I never drive in anyway) not sure there are any inherent benefits in dry warm conditions.
 
#9 · (Edited)
Curious, what makes it more difficult to install the LSD in the Cayman over, say, any other FWD car's transmission? Btw, I did wind up purchasing this from the eBay vendor so I'm one of those two. I got sidelined by getting my '95 Mitsu Evo III in decent mechanical shape the last few months so I haven't gotten around to installing the GT4 LSD.

As for the benefits, a mechanical LSD will aid with putting traction to the tarmac at the exit of a turn as you lean into the accelerator to power your way out past the apex. In his review of the 718 CS vs the BMW M2 and Audi TT RS, Jethro Bovingdon for Drivetribe noticed a definite issue in that regard with the open diff during the track test.


Go to 4:35 if you want skip straight to the 718 CS test and his impressions of the car are after the lap.
 
#10 · (Edited)
My GTS has PTV/LSD but I've driven non-PTV/LSD caymans before and my thinking is the well balanced mid-engine does not need the LSD so much, unlike the front engined cars. I think on the track there is more to be gained by tyre choice, suspension adjustments and improved driver technique. However, the LSD does make a difference on mountain roads with uphill tight hairpin switch backs where the inner wheel becomes very light or air born on the cambered road and it is difficult to get traction down. The Porsche traction control will deal with this but you will be a bit slower out of those corners without the PTV/LSD car but everywhere else performance will be similar.

I believe the ebay diffs are the OS Giken LSDs which have been around for a long time. However, they only fit manual 981/982s and there is not after markert option for PDK as far as I know.

P.S. of course in wet or slippery conditions the LSD is also useful.
 
#11 ·
Agree with Don. My S does not have PTV/LSD. On tight mountain pass roads with 2nd gear corners at high lateral loads, I can get lots of inside wheel spin on corner exit without the car trying to go sideways as the outside wheel has good grip. I doubt this would be an issue at higher speeds on a track. You can drive around it with judicious throttle application, but really you are just going slower, as the car has no slip angle, and would take some extra acceleration torque if you could move the torque to the outside wheel with PTV/LSD.

I got my car 2nd hand, so could not choose options. My car has some good options, but if there was one thing I wish it had, it would be the PTV/LSD.