[oceanview]

After quite a long time I decided to finally invest in an LSD. Since the M Performance LSD had been invited a while ago, I was put into "decision mode".
Long story short, I finally decided to go for the Quaife. Not least thanks to the recommendation of Krelle

So I picked up the LSD'ed car today and took it to the ride back home.
The way took me to a little pass road I've driven many times. Under dry conditions, most of the curves can be driven, with an entering speed of about 25-30 mph.
Without the LSD, when pushing the pedal at that situation, the car would clearly tend to understeer, until DSC chimed in and would slow down the car and bring it back from understeer into my wanted direction.

So here I come again but now with the LSD in the back. First corner, passing turn in point, at slow safe speed far away from critical understeering, then pushing the gas. Car speeds up, I expect DSC lamp to come on any moment, but far away! Car grabs into my decided direction. First smile on my face. Second corner already in front, ok let's see again. More in speed, turn in point, earlier back to gas, fantastic! Feels like back wheels steer into corner.
With every corner I get more confidence, car is controllable in an easy logic way. The more gas, the more the car turns into corner. Oversteering can be corrected by just lifting the gas pedal.
Smile on my face!

The car does feel like a whole new car. Understeering while speeding up exiting a corner is gone.
Just to be clear if you're to fast, you're to fast. Can't beat physical laws!
But the car now turns into the direction I want when I push the gas.

I haven't reached any limit or critical point, as I was driving on public road under dry conditions. I really look forward to experience wet road conditions in a few days. Slippery roads will show better on how LSD works and when DSC/DTC will jump in.

But clearly, should have done the LSD decision sooner!

[PeterPure]

Hmm i drive always with traction fully off. When i gas it in corner i never get understeer but oversteer which i can correct with my throttle input as well. I have f20 m135i with e-diff. Maybe you should try disable tractiin control as well.

[Polo08816]

Great review.

[oceanview]

Originally Posted by Darkhold

Hmm i drive always with traction fully off. When i gas it in corner i never get understeer but oversteer which i can correct with my throttle input as well. I have f20 m135i with e-diff. Maybe you should try disable tractiin control as well.

Traction control "off" won't help from understeer. Maybe it is because of the 225/255 tire setup, that front has so much less grip than rear.
I've "raced" the car on a small track a while ago. LSD is a great improvement compared to what I experienced then.

[Krelle]

Originally Posted by oceanview

Traction control "off" won't help from understeer. Maybe it is because of the 225/255 tire setup, that front has so much less grip than rear.
I've "raced" the car on a small track a while ago. LSD is a great improvement compared to what I experienced then.

Once again, Congratulation! Makes me happy you´re satisfied and I didn´t just persuade into something.

As mentioned before. Without the Quaife LSD I did a 360 coming on to the freeway under hard acceleration. Same spot was tested twice after having mounted the LSD, without spinning.

The mentioned understeer can be helped somewhat by adjusting your dampers and camber set up.
My traction is more or less in "off".

The LSD is by far the best mod on my car. No doubt!
/Krelle

[oceanview]

Originally Posted by Darkhold

Hmm i drive always with traction fully off. When i gas it in corner i never get understeer but oversteer which i can correct with my throttle input as well. I have f20 m135i with e-diff. Maybe you should try disable tractiin control as well.

What I mean is, that when I drive a corner fast and then accelerate in a moderate but consequent way (just pushing more to the limit without to hard of gas pedal action) the car tends to understeer (without LSD).
This has changed now with the LSD. The car "turns" into the corner much better, giving you a very precise steering feeling.
(Again, Car is still in normal "Comfort" or "Sport" mode with DSC on and DTC off. DSC in above situation with LSD is not active/regulating my driving speed)

Originally Posted by Krelle

a) Once again, Congratulation! Makes me happy you´re satisfied and I didn´t just persuade into something.

b) As mentioned before. Without the Quaife LSD I did a 360 coming on to the freeway under hard acceleration. Same spot was tested twice after having mounted the LSD, without spinning.

c) The mentioned understeer can be helped somewhat by adjusting your dampers and camber set up.
My traction is more or less in "off".

d) The LSD is by far the best mod on my car. No doubt!
/Krelle

a) I had now doubt, that LSD is a good choice, as I used to have one in my 318is E30 back 20 years ago. I was not sure if I should go for MPLSD or Quaife or else and on DIY or by dealer. There is only one Quaife dealer in our area, so I had to go with him, which seemed to be a good choice.

b) Did you switch off DSC to make your car spin on the freeway?

c) How could that be done with the Adaptive M Suspension installed? Changing the springs seems the only option to me. Guess won't do that for now! I will now install the strut bar and see if I get some improvement also regarding understeering. However the LSD solved much of that spongy feeling.
I also run RFT on my summer and winter tires. So the Pirellis may not be the best possible setup. Will decide next spring if I skip them for non-RFT and get a tire repair kit. But summer tire decision will be another forum topic. I'm not a fan of Michelin nor Pirelli and would rather go with Dunlop SP Sport Maxx GT or ContiSportContact 5P.

d) Fully agree. The LSD is an invisible, non-bling-bling "tuning". Can't impress your neighbors with it unless you take 'em on a ride around the corner and scare the s**t out of them! It's a complete driver egoist part

[Krelle]

b) I almost always switch off the DSC.

c) Sorry, I forgot you have the Adaptive M Suspension installed.
How about Eibach springs?
I run Michelin and is satisfied. No runflat tires in the summer time.

d) Egoist part ? It´s simply just necessary to get the optimum out of the car.
Smiling is also very healthy!

[PeterPure]

I ordered a quaife too. Must see for myself how much it helps...

[oceanview]

good choice! With all your tune, and with the shorter wheel based F20, you should see even more progress with the LSD.
I would recommend to NOT switch off the DSC at the beginning, so you have some safety when testing the LSD in the corners (unless you are on a track away from public traffic)

Let us know your thoughts once you have it!

[PeterPure]

Originally Posted by oceanview

good choice! With all your tune, and with the shorter wheel based F20, you should see even more progress with the LSD.
I would recommend to NOT switch off the DSC at the beginning, so you have some safety when testing the LSD in the corners (unless you are on a track away from public traffic)

Let us know your thoughts once you have it!

But I already drive now all the time with DSC fully off. I will see then first with DTC mode to see how far I can go without the DME intervening. Will keep you posted.

[Krelle]

Hi DH,
You won't regret this decision.
Try checking it out when you go through curves on the track!

[PeterPure]

Originally Posted by Krelle

Hi DH,
You won't regret this decision.
Try checking it out when you go through curves on the track!

Will do