Preferred track setting - DSC, MDM or OFF?

[nicknaz]

Originally Posted by shaftwhy

maybe just more practices.

doesn't everyone ?

[Absurdium]

DSC off for me but like others have said; MDM for when getting used to a new track. I will add though that through my experience, there is so much more grip with DSC fully off. When in MDM, the system will frequently cut power, upsetting the car in the middle of the corner and making it feel like there's not a lot of grip. Now theoretically, MDM should only be intervening when you're very close to the limit of adhesion so I thought maybe I just need to ease in the throttle more delicately. However after turning DSC off, I discovered that this is not the case. It is very hard to develop any meaningful rotation with MDM on using the throttle. You realize just how much mechanical grip there is once the DSC is off and no longer playing interference. However, you do need to be diligent when applying power with DSC off, especially if you have an early build/early software car as those are tuned to deliver torque more aggressively.

[CanAutM3]

Originally Posted by Absurdium

DSC off for me but like others have said; MDM for when getting used to a new track. I will add though that through my experience, there is so much more grip with DSC fully off. When in MDM, the system will frequently cut power, upsetting the car in the middle of the corner and making it feel like there's not a lot of grip. Now theoretically, MDM should only be intervening when you're very close to the limit of adhesion so I thought maybe I just need to ease in the throttle more delicately. However after turning DSC off, I discovered that this is not the case. It is very hard to develop any meaningful rotation with MDM on using the throttle. You realize just how much mechanical grip there is once the DSC is off and no longer playing interference. However, you do need to be diligent when applying power with DSC off, especially if you have an early build/early software car as those are tuned to deliver torque more aggressively.

From what I have read and seen, the stronger torque delivery of the earlier tunes is all below 2500RPM, which is pretty much irrelevant on track.

[The Choosey begger]

Originally Posted by CanAutM3

From what I have read and seen, the stronger torque delivery of the earlier tunes is all below 2500RPM, which is pretty much irrelevant on track.

Not irrelevant if you got 285/30-18's with 50% tread left and an overall diameter of less than 24.8". You can still break traction above 2,500 rpm.

[Absurdium]

Originally Posted by CanAutM3

From what I have read and seen, the stronger torque delivery of the earlier tunes is all below 2500RPM, which is pretty much irrelevant on track.

Originally Posted by anglo

That's true but what about from the paddock to the pits! Jokes aside, that's a good point and it reinforces the idea that this is definitely a car that works best with DSC off. However I've also read that the pedal mapping for the later cars are less aggressive but this was just feedback from owners so it may just be a placebo effect as well.

Not irrelevant if you got 285/30-18's with 50% tread left and an overall diameter of less than 24.8". You can still break traction above 2,500 rpm.

I think he just meant what I was saying doesn't necessarily apply to track driving as you shouldn't ever be that low in the Rev ranges, not that the F8X has any issue breaking traction.

[Absurdium]

Accidentally double posted.

[drroc]

Originally Posted by shaftwhy

Just tried this today on public roads and wasn't very successful.

My usual heel position is in front of brake pedal (or very close). When I switch between brake and throttle back and forth I don't change heel position at all. I just flip my foot over with heel as an anchor.

This position has a few advantages to me:
1. Hard to mistake throttle for brake (for public road) because they have different foot positions. Brake is forward and hard, throttle is a little side way and gentle.
2. Quick switch between brake and throttle as heel doesn't need to move.
3. Consistent heel position on track. Since the switch from brake to throttle normally happens mid-turn (trail brake) with quite a bit lateral g, keeping heel anchored helps to achieve consistent movement from brake pedal to throttle pedal. Before using this position, I have experienced quite a few switches with inconsistent heel position which gave totally wrong feeling sometimes. Similar applies switch from throttle to brake: If the heel position changes during brake, then it is harder to modulate the brake, especially for trail brake.

I understand if you always anchor the heel against throttle hinge, then the heel position for throttle is indeed consistent. However it doesn't really give a consistent heel position for brake. Also it really feels the switch between pedals is slower as you need to find different heel positions for brake and throttle. Also for me, I can have too much movement and end up stepping on the foot well a little bit as well.

CanAutM3 , any further tips for this?

I suppose the best might be left foot braking so each foot has its permanent anchor

One thing which works quite well for me is to concentrate on trying to use my big toe to press on the throttle. This forces you to push the pedal at the top, thus giving you effectively more travel. More travel equates to finer throttle adjustments.

[MPOOR]

Originally Posted by CanAutM3

That's the thing, your foot might "be getting on the throttle earlier", but the engine is not delivering the power any earlier because of the damping effect, so what's the point? I rather have my foot control the power delivery than the software, like this I can get either smooth or sharp transitions depending on what I want. Sport+ is far from being an on/off switch, it is in fact very linear, but it does respond immediately to any movement. It is only a question of properly calibrating your right foot.

As a tidbit, I often notice that when students struggle with smooth throttle control it is related to the foot position on the throttle pedal. On throttle pedals that are hinged at the bottom like we have on our cars, it is preferable to have the entire foot resting flat on the pedal with the heel against the hinge. If the heel is away from the hinge with only the toes pressing on the middle of the pedal, a smaller foot movement will result in a larger pedal movement making it more difficult to be precise. Also, it is difficult to position the heel at exactly the same distance from the pedal when the foot is moved from the brake to the throttle, so depending on the heel position, a different foot movement will result in a different pedal movement, making it very challenging to program muscle memory. Further, when the heel rest away from the hinge, the toes need to slip up and down the pedal as the pedal is moved and the friction between the shoe sole and the pedal can cause jerkiness in the movement. Might not be the case for you, but worthwhile mentioning.

Very good point. Everything starts from a proper positon.

I also agree ~ you need turn off the Traction control for maximum performance.

And be super smooth ~ especially with F80 F82 M3 M4

[MRV99]

After looking at my throttle traces after running the Windy City autobahn event it was showing just how much throttle the MDM was cutting the power. I was way past apex with gentle throttle and dead straight and still the power was cut. So this last event I ran with MDM/DSC off for the first time. Man did it make a difference. Good for 3 seconds of my fastest time. The F80 chassis communicates very well and if the car was the least bit out of shape the car let you know with plenty of time to correct. With all the horror stories and videos of guys snapping loose on the street I was a bit hesitant. Just need to start off a bit slower and then let it rip.

I also just remembered another issue I was having as well as a few other guys with F80's running MDM/DSC on. When you were braking from 100+ mph, the car seem to be floating and not really hitting down. The initial
brake application, the car would be light on the ass and feel unstable. Once the car was slowed down a bit, it seem to really start to bite. Once I hand the nannies OFF, this sensation went away to never return. I have a feeling the DSC was causing the momentary unsettling feeling while braking.

[CanAutM3]

Originally Posted by MRV99

After looking at my throttle traces after running the Windy City autobahn event it was showing just how much throttle the MDM was cutting the power. I was way past apex with gentle throttle and dead straight and still the power was cut. So this last event I ran with MDM/DSC off for the first time. Man did it make a difference. Good for 3 seconds of my fastest time. The F80 chassis communicates very well and if the car was the least bit out of shape the car let you know with plenty of time to correct. With all the horror stories and videos of guys snapping loose on the street I was a bit hesitant. Just need to start off a bit slower and then let it rip.

^ This

[Harpinc]

If you are asking this questions, please make sure and leave all of the nannies on.

[Dr._Who]

Originally Posted by ptyf80

I just bought my f80 on June 16, coming from a Lexus ISF i can tell that this car is something else. I got it with 7,000miles and loaded with Dinan S2, M Performance Titatunium Exhaust, fabspeed downpipes and x-pipe (these last two are not installed currently, since with the downpipes previous owner got an "overboost check message" during a track day.

I used to track my ISF and the M3 will be used for the same. So on july the first went to our local (only one track in the entire country, I live in Panama). Got the car with the second pair os wheels (also came with the car), i removed the hoosiers that were installed and installed a DOT Toyo´s R888R 245 35 19 and 275 35 19.

first laps took it slowly and used DSC full on, but its amazing how much power get lost when DSC is on, so a few laps later switched to MDM. I think tires were too narrow because the car was power sliding all over the place, so DSC full off was not an option.... at least for now.

Maybe in my next track day with wider tires ( im considering going to 18 with 10.5 and 11 wheels and 275 35 and 305 30 with maybe the same R888R´s or might evaluate NT01 or even but expensier Trofeo´s R.

I need more grip and then ill will turn the DSC full off.

Thoughts???

This is my first post. here is a video of a few laps during that track day


PTYF80
2016 F80 M3 - Mineral Gray - DinanS2
Panama City, Panama

Hey,

Congrat's!

I live in Guatemala City! One track here, also! WooHoo!!


F.Y.I.: https://f80.bimmerpost.com/forums/sh...0#post23278210


Cheers!


P.S.: Nice track layout.