One of the cars Olly drove was mine

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I have to ask, have you driven a RWD car with a plated LSD before Oli? I did notice that at normalish speeds it did want to understeer a little, and this is something someone else commented on who was originally looking at a 968 Club Sport. It took me a good while to commit in the corners over my S2 but it did tighten up with speed and there is no way I'd have gone that fast in some bends in my S2 as an owner of a low mileage (well, 78k) S2 also said to me. It went from feeling like it may lose grip to suddenly gripping harder as the diff seemed to be kicking in. I really should have taken that car on a trackday before I left to see where the limits ended, although they did reduce dramatically when cold with the LSD probably not helping matters! Trying to go sideways at 40MPH with a little boost anyone, in cold and very wet conditions?
Even lowered by quite a way mine wasn't too bad on country roads. If I'd have kept the car I would have raised the car 10mm all round, even if it did look the business at its height!
My RST with an LSD was no different, albeit the *refurbished* viscous variety. Go into a corner with no throttle and the front would want to wash out, even with Nankang NS-2R tyres warmed up. With a bit of thottle the line tightened up more than I have had in any other FWD car and I've had a few without LSDs, to the point rear end grip would become an issue if I lifted off. That was on Ledas @ £1.2k when I last checked, but IMHO it was a little firm on the road, but an improvement over tired RS Turbo shocks by quite a way.
The M3 feels 'normalish' but I may to get the diff checked out. OTOH it is quite easy to hold a drift, but I would not know about that...