Two questions

[ezrider]

Does the E89 have a limited slip differential? The roads on Long Island are paved by children. Has anybody tried a series 55 tire instead of 45? Trying to soften the ride. Any other suggestions?

[B21]

Originally Posted by ezrider

Does the E89 have a limited slip differential? The roads on Long Island are paved by children. Has anybody tried a series 55 tire instead of 45? Trying to soften the ride. Any other suggestions?

No LSD was ever fitted to any E89 model..

I’ve had Quaife LSDs fitted to both mine..with very good results..expensive solution…but if you have a quest for speed and assured handling a great product…

If you are in need of a 55 profile you are in the wrong car…I assume you have ditched the run flats already ?

[MRCW]

Originally Posted by ezrider

Does the E89 have a limited slip differential? The roads on Long Island are paved by children. Has anybody tried a series 55 tire instead of 45? Trying to soften the ride. Any other suggestions?

Check the air pressure. When I get any of my vehicles back from service, air pressure is usually higher than specified.

Play around with air pressure a bit. On low profile tires it can make a difference. I suppose you could try 17" wheels and a bit higher profile... but it's counter to the design of the car

[GerryC]

Originally Posted by ezrider

Does the E89 have a limited slip differential? The roads on Long Island are paved by children. Has anybody tried a series 55 tire instead of 45? Trying to soften the ride. Any other suggestions?

As others said, no LSD.

The best option for a better ride is ditching the run-flats. For me, switching to Michelin PS4 A/S non-runflats made a huge difference in ride. Of course, there's no spare so get a mobility kit (BMW or aftermarket).

[etropic]

Originally Posted by B21

No LSD was ever fitted to any E89 model..

I’ve had Quaife LSDs fitted to both mine..with very good results.

Curious what the interplay of DSC and a actual LSD is like?

[B21]

Originally Posted by etropic

Curious what the interplay of DSC and a actual LSD is like?

All works seamlessly….you can optionally code off the e-diff function within the suite of various DSC functions..some folks get very heated by the differences between plated diffs and helix geared torque biased diffs such as Quaife…

There’s a track obtuse argument that the torque biased diffs are not so good on tracks where if a wheel lifts the LSD function doesn’t work…in that mode keeping the e-diff option may help..

On the road, especially in the N54 and tuned N20 engines the torque can overpower the rear wheels especially in corners..

I’m running 400 BHP now and even on quite damp roads the stability is amazing in the sense that there is just not the drama that previously happened..of course with e-diff switched on and especially then if the car yaws the DSC shuts the engine down to preserve stability but results in impeded progress.

If you drive in a normal road driver fashion it probed a complete waste of time (unless you drive in snow)…however if you like to press on and conditions permit it’s your best handling aid after decent tyres and decent suspension..

[ezrider]

Thanks to all. One more question. What is a mobility kit?

[paris1]

Originally Posted by ezrider

Thanks to all. One more question. What is a mobility kit?

The short answer is "a 12V emergency tire pump and a can of Slime". With maybe a tire plug kit thrown in for good measure!

[Marcoose]

Motorbike kits work great. And a cigarette-lighter air pump.