Advice regarding E46 DSC on track.
Discussion
Hey everybody,
I'm hoping that some experienced track day drivers can come along and give me some insight into my question, particularly some with experience in an E46.
I was at Oulton Park on Saturday for a javelin track day, weather was great and the day in general was just excellent.
My 330 has coilovers, Mich PSS, rear stripped out etc. I've done the geo myself and so the handling for me is great. What I was experiencing in the car on Saturday was that on the exit of some corners the car seemed to lack in power, out of the corner of my eye I could see the DSC light flashing in the centre of the dash which I'm assuming means the car is detecting some wheel slip? The car though was by no means out of shape and was just being accelerated hard after the apex of the corner.
My question is now in this case is the DSC becoming intrusive and would I benefit from turning the dsc off and what advantages/disadvantages would this give me?
I'm hoping that some experienced track day drivers can come along and give me some insight into my question, particularly some with experience in an E46.
I was at Oulton Park on Saturday for a javelin track day, weather was great and the day in general was just excellent.
My 330 has coilovers, Mich PSS, rear stripped out etc. I've done the geo myself and so the handling for me is great. What I was experiencing in the car on Saturday was that on the exit of some corners the car seemed to lack in power, out of the corner of my eye I could see the DSC light flashing in the centre of the dash which I'm assuming means the car is detecting some wheel slip? The car though was by no means out of shape and was just being accelerated hard after the apex of the corner.
My question is now in this case is the DSC becoming intrusive and would I benefit from turning the dsc off and what advantages/disadvantages would this give me?
As above, turn the DSC off. All the way off, ie hold the button down for 5 seconds until the slip light comes on and stays on permanently.
when i was tracking old E46s and then an E85, i'd normally do the first couple of laps with traction and dsc on, but then its off for the rest of the day.
though, one thing to note, is make a note of when the slip light is flashing, because thats where and when the car will be spinning when you've turned it off. BMWs love to light up the rears exiting tight corners.
when i was tracking old E46s and then an E85, i'd normally do the first couple of laps with traction and dsc on, but then its off for the rest of the day.
though, one thing to note, is make a note of when the slip light is flashing, because thats where and when the car will be spinning when you've turned it off. BMWs love to light up the rears exiting tight corners.
Mine did the same, it's not really setup for track work, and unless you want to go to the trouble of swapping out the ABS unit for the M3 version and have it flashed with the Z4M map? (former friend had this done if i recall) it allows a bit more slip.
If not, press and hold for 3 seconds to turn it off fully , which is shown with orange lights in the DSC and hand brake locations, and enjoy the car's true handling dynamics.
If not, press and hold for 3 seconds to turn it off fully , which is shown with orange lights in the DSC and hand brake locations, and enjoy the car's true handling dynamics.
Thanks for all the help and advice everybody, really helpful.
It seems to be activating any time the car is under really hard acceleration coming out of tight corners. Long sweeping bends which are quick it won't activate at all, like others have said it doesn't seem to like hard cornering coupled with hard acceleration out of the corner.
Looking forward to get out on the next track day now and see how it is without it on.
It seems to be activating any time the car is under really hard acceleration coming out of tight corners. Long sweeping bends which are quick it won't activate at all, like others have said it doesn't seem to like hard cornering coupled with hard acceleration out of the corner.
Looking forward to get out on the next track day now and see how it is without it on.
It's simply that your car doesn't have a limited slip diff (LSD) so you are getting the typical symptom of the inside rear wheel starting to spin when coming out of tight corners. The DSC will naturally kick in to reduce this wheelspin.
Whether DSC is on or off, without a LSD you'll be quicker by applying less throttle in those circumstances.
With DSC on the car will cut power; with DSC off the inside rear wheel will start spinning which also slows the car (the spinning wheel takes power away from the wheel with grip).
Whether DSC is on or off, without a LSD you'll be quicker by applying less throttle in those circumstances.
With DSC on the car will cut power; with DSC off the inside rear wheel will start spinning which also slows the car (the spinning wheel takes power away from the wheel with grip).
Edited by braddo on Tuesday 23 November 17:00
braddo said:
It's simply that your car doesn't have a limited slip diff (LSD) so you are getting the typical symptom of the inside rear wheel starting to spin when coming out of tight corners. The DSC will naturally kick in to reduce this wheelspin.
Whether DSC is on or off, without a LSD you'll be quicker by applying less throttle in those circumstances.
With DSC on the car will cut power; with DSC off the inside rear wheel will start spinning which also slows the car (the spinning wheel takes power away from the wheel with grip).
I did ask this earlier as the first thing most of the guys I track with did to their's was to add an MFactory LSD, or swap in an M3 rear end.Whether DSC is on or off, without a LSD you'll be quicker by applying less throttle in those circumstances.
With DSC on the car will cut power; with DSC off the inside rear wheel will start spinning which also slows the car (the spinning wheel takes power away from the wheel with grip).
Agreed. Unless you change your driving style, i predict many spins in your future! Hard acceleration and exiting tight turns dont mix very well.
If conditions are tricky, youd be wise to get the car in a straight line, then gently feed in the power. In the damp an e46 will go sideways if you so much as look at the throttle funny.
If conditions are tricky, youd be wise to get the car in a straight line, then gently feed in the power. In the damp an e46 will go sideways if you so much as look at the throttle funny.
breezy said:
The traction control in some cars can be quite sophisticated, in yours it will be incredibly basic.
As above, turn it off but be ready to adapt your driving style. If you are used to mashing the throttle and letting the car sort things out, then it will be a big change.
As above, turn it off but be ready to adapt your driving style. If you are used to mashing the throttle and letting the car sort things out, then it will be a big change.
This thread asked for advice on Dynamic Stability Control not Traction Control...
PGNSagaris said:
Hi OP.
I hated having it on when on track. (It was only on when I forgot to turn off)
Makes the car unpredictable, especially when having fun.
On track turn everything off. Best way to learn
Agreed. And the e46 is a nicely balanced chassis, so shouldn't do anything unexpected. I hated having it on when on track. (It was only on when I forgot to turn off)
Makes the car unpredictable, especially when having fun.
On track turn everything off. Best way to learn
bigothunter said:
breezy said:
The traction control in some cars can be quite sophisticated, in yours it will be incredibly basic.
As above, turn it off but be ready to adapt your driving style. If you are used to mashing the throttle and letting the car sort things out, then it will be a big change.
As above, turn it off but be ready to adapt your driving style. If you are used to mashing the throttle and letting the car sort things out, then it will be a big change.
This thread asked for advice on Dynamic Stability Control not Traction Control...
Andrew-b90y3 said:
I was experiencing in the car on Saturday was that on the exit of some corners the car seemed to lack in power, out of the corner of my eye I could see the DSC light flashing in the centre of the dash which I'm assuming means the car is detecting some wheel slip? The car though was by no means out of shape and was just being accelerated hard after the apex of the corner.
Traction control is part of the dsc system and it’s not a big leap to suggest that it’s the part that is active here. I’d say that any of these systems can be a handy safety net for less experienced drivers but they are designed to intervene early so can become intrusive as you push on track, especially on the earlier versions like a 46.
As others have suggested, try turning it off, go careful and start by pushing on the corners that have a bit of room to get the feel for it.
Steve H said:
Traction control is part of the dsc system and it’s not a big leap to suggest that it’s the part that is active here.
Traction control prevents wheelspin at launch from rest, unless the tarmac surface is very slippery or the car has abnormally high wheel torque. Once underway from the pit lane, traction control has limited or no role to play.Here's a simple overview of BMW's DSC system. This may help your understanding:
I think you're going a bit far with your conclusions there. Traction control gets involved any time there's a loss of traction (clue is in the name). If you're driving 'normally' on the road, then you're probably correct. But in track driving you'll often have enough lateral load on throttle to cause the tcs to intervene - both in terms of the inside wheel being unloaded, and if the back end is out that will tend to be detected as slip.
DSC may well go above and beyond that, but it/similar systems do interact with the TC and use it as part of their control strategy.
DSC may well go above and beyond that, but it/similar systems do interact with the TC and use it as part of their control strategy.
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