M3 corner/high speed stability issues

[CanAutM3]

Originally Posted by Iceman1

What specs did you align to? (Camber/caster/toe settings)

Before the camber plates, I had everything put to the OEM nominal setting. After the camber plates, I went with -2.5 front and -1.6 rear camber with all other parameters to OEM specs.

[mm767cap]

Originally Posted by Strongbad

Hi everyone.

Picked up a '17 M3 ZCP a few months ago and I have been noticing that when I am cornering (ie. freeway on/off ramp) the car will sometimes get unsettled and twitch in the middle of the corner (feels like a split second of understeer in the middle of the corner before the car corrects itself). This is happening at speeds of 35-45 mph and happens when I am both on and off the throttle so its not something that has to do with coming into the corner with too much speed. Needless to say this is very unnerving and makes me apprehensive about driving the car the way it is meant to be driven. I am sending the car in to have the alignment checked on Thursday to see if that could be the issue.

I used to have a 2015 M4 and never noticed this behavior so I am wondering if it is a product of having the competition pack or if something is wrong with my car. ( I am leaning toward the latter.)

Another, possibly related, issue I am having is that this car feels much less stable at high speeds (above 85MPH) than the M4 did. I have never driven another F80 M3 so I am not sure if the M3 is inherently less stable at high speeds than the M4 or if it could be another symptom of the same issue that I am having while cornering.

My car also came from the dealer with the front splitters/lip installed but does not have the M performance spoiler installed so I am wondering if that is messing with the stability of the car at higher speeds because I have read that BMW recommends installing both the splitters and spoiler together.

Sorry for rambling but trying to see if anyone had similar issues and how they were resolved.... Hoping the alignment fixes it but we will see.

Back to your original post here, Strongbad. I've now tried this several different things, and in my car the suggestion someone had on here to turn off the DSC was the ticket. That "wheels rolling off the tires" feeling is completely gone and the front end bites rather hard with throttle lift when I have the DSC in MDM. Very very interesting. When you get the car back, see if you experience the same in MDM mode.

[Iceman1]

Originally Posted by CanAutM3

Before the camber plates, I had everything put to the OEM nominal setting. After the camber plates, I went with -2.5 front and -1.6 rear camber with all other parameters to OEM specs.

Did you the get the additional stability you mentioned with just a OEM spec alignment before the camber plates?

The additional camber with the plates, that's mostly to prevent tires from prematurely cording on the track right? Or does that add any additional stability?

[nicknaz]

Originally Posted by Iceman1

Did you the get the additional stability you mentioned with just a OEM spec alignment before the camber plates?

The additional camber with the plates, that's mostly to prevent tires from prematurely cording on the track right? Or does that add any additional stability?

Hi, I would also suggest adding more rear toe in. My car was slightly more toed in than the factor spec and I liked it better. It came with very little toe in from factory (basically zero toe) and that was tougher to drive (especially on stock pss after they were overheated 3-4 laps in). I could see how some owners would find this "twitchy".

Imho, a lot of this thread is from owners who just want to press "'mdm mode" and then go driving.

Hopefully someone from Bmw read this and realizes they need to be a lot more thoughtful on the setup of the cars coming out of the factory, have a multi step driving aid traction control and will let owners slide a bit instead of being so intrusive, and putting in an option for wider R tires from factory.

The car would have gotten much better journalist reviews and prevent this type of post from happening in the first place.

This isn't a Porsche GT car were owners can reasonably be expected to drive straight from the dealership to their usual race prep shop to be aligned and corner balanced right away....

[CanAutM3]

Originally Posted by nicknaz

Imho, a lot of this thread is from owners who just want to press "'mdm mode" and then go driving.

Hopefully someone from Bmw read this and realizes they need to be a lot more thoughtful on the setup of the cars coming out of the factory, have a multi step driving aid traction control and will let owners slide a bit instead of being so intrusive, and putting in an option for wider R tires from factory.

The car would have gotten much better journalist reviews and prevent this type of post from happening in the first place.

This isn't a Porsche GT car were owners can reasonably be expected to drive straight from the dealership to their usual race prep shop to be aligned and corner balanced right away....

...see M4 CS

[nicknaz]

Originally Posted by CanAutM3

...see M4 CS

I guess that is true. All the suggestions I made are covered by the CS.

But at a big $ and mixed reviews (aka brand damage) for all the early cars

[CanAutM3]

Originally Posted by nicknaz

I guess that is true. All the suggestions I made are covered by the CS.

But at a big $ and mixed reviews (aka brand damage) for all the early cars

I agree, the M4 should have first been launched with all the CS goodies.

[Iceman1]

Originally Posted by nicknaz

Hi, I would also suggest adding more rear toe in. My car was slightly more toed in than the factor spec and I liked it better. It came with very little toe in from factory (basically zero toe) and that was tougher to drive (especially on stock pss after they were overheated 3-4 laps in). I could see how some owners would find this "twitchy".

Imho, a lot of this thread is from owners who just want to press "'mdm mode" and then go driving.

Hopefully someone from Bmw read this and realizes they need to be a lot more thoughtful on the setup of the cars coming out of the factory, have a multi step driving aid traction control and will let owners slide a bit instead of being so intrusive, and putting in an option for wider R tires from factory.

The car would have gotten much better journalist reviews and prevent this type of post from happening in the first place.

This isn't a Porsche GT car were owners can reasonably be expected to drive straight from the dealership to their usual race prep shop to be aligned and corner balanced right away....

Thanks, buying a $100K variant in not necessarily an option for those buying an $80K car.. if it's a specific alignment the factory should have paid more attention to, most average F8X buyers can go to their local alignment shop, spend ~$100 and get a better set up car and have a better experience!

I see posts on this thread from people stating their F8X did not feel stable at 85mph.. I have a Toyota Venza that feels pretty stable at 95-100 mph... so I'm are not even sure where some folks are coming from on a car that is the global benchmark of Grand Touring..

[Ilikemike]

Originally Posted by CanAutM3

Before the camber plates, I had everything put to the OEM nominal setting. After the camber plates, I went with -2.5 front and -1.6 rear camber with all other parameters to OEM specs.

CANAUT, from your experience, do you think it was worth doing the camber plates without lowering the car?

[nicknaz]

^ if I kept my f80 I would have done camber plates on stock suspension to save the outer shoulder of front tires. I was about to cord the stock tires in 3-4 DEs

[CanAutM3]

Originally Posted by Ilikemike

CANAUT, from your experience, do you think it was worth doing the camber plates without lowering the car?

Most definitely.

I had camber plates on my E46 and E92 with an otherwise stock suspension. The main driver for me getting plates is to improve tire wear at the track. The only reason I went with springs on my M4 is for looks (I was not very fond of that "front fender gap"). I got a very good deal on an Eibach kit (spring rates are quite close to stock) and installing them at the same time as the camber plates meant install cost at almost nothing.

[Ian1973]

I haven't felt much understeer in this car, I can't think of a time at all honestly. I drive in the warm months without traction control. What I have noticed is the lack confidence in the rear of the car, you initiate turn in, get near the apex and add some throttle, the thing always has a transition point that feels like the rear is going to break free. I agree with CanAut, I think this is the solid mounted subframe.

Funny story, I took my teenager out 2 months ago after just putting my summers back on to teach her how to drive a manual. We were in parking lots for a few hours as she tried to learn. Unfortunately for me, the ambient temp was unusually cold for the time of year(~28 deg F), as we headed home, I was explaining to her throttle position versus available traction, I was going to swing the rear out a little out of a roundabout, well bad move in cold temps and PSS, immediately it swung out to far and I could feel the fronts lose traction. I knew there was no saving it, off the road we went and settle in a depression on the side the road. Didn't hit anything, but the depression did a number.

The point of the story, I just got the car back yesterday and took it out for some spirited driving today and that feeling we all have felt is now scaring the crap out of me, that rear transition to throttle input mid corner. To the point I have it MDM for the first time in 2 years of ownership. It didn't feel very confidence inspiring today.

Yet I was following a new Camaro around a local lake(ie, some fun roads) on my sportbike and he was in it, driving pretty insanely for a Camaro. Granted he lived in the area I'm sure and knows the roads, where I didn't, but he was going pretty good and looked to be pretty dam planted.

[drkeng]

just curious, in my 435 on the last stretch of highway (see map below) before my exit it is possible to hit triple digits (so I'm told) and on the offramp marked with the finger one can go about 40 tops without a lot of tire squealing, but the car feels stable. I think the "recommended" speed limit is 25, but those are yellow signs, highly conservative, geared to minivans and the like

what could I expect in an M4? I would think 40-45 on the offramp wouldn't be a problem. I actually think I did it many moons ago in an E46 M3 w/ SMG.
we see posts of people taking their new M's on the autobahn at triple digit speeds without complaints or problems. and, of course, many track their cars. so what's up with all the talk of instability?

[TRZ06]

Originally Posted by Ian1973

I haven't felt much understeer in this car, I can't think of a time at all honestly. I drive in the warm months without traction control. What I have noticed is the lack confidence in the rear of the car, you initiate turn in, get near the apex and add some throttle, the thing always has a transition point that feels like the rear is going to break free. I agree with CanAut, I think this is the solid mounted subframe.

Funny story, I took my teenager out 2 months ago after just putting my summers back on to teach her how to drive a manual. We were in parking lots for a few hours as she tried to learn. Unfortunately for me, the ambient temp was unusually cold for the time of year(~28 deg F), as we headed home, I was explaining to her throttle position versus available traction, I was going to swing the rear out a little out of a roundabout, well bad move in cold temps and PSS, immediately it swung out to far and I could feel the fronts lose traction. I knew there was no saving it, off the road we went and settle in a depression on the side the road. Didn't hit anything, but the depression did a number.

The point of the story, I just got the car back yesterday and took it out for some spirited driving today and that feeling we all have felt is now scaring the crap out of me, that rear transition to throttle input mid corner. To the point I have it MDM for the first time in 2 years of ownership. It didn't feel very confidence inspiring today.

Yet I was following a new Camaro around a local lake(ie, some fun roads) on my sportbike and he was in it, driving pretty insanely for a Camaro. Granted he lived in the area I'm sure and knows the roads, where I didn't, but he was going pretty good and looked to be pretty dam planted.

It's the stock rebound tuning on the shocks.

After adding coil-overs all (and I do mean ALL) the rear-end nastiness is gone.

[TRZ06]

Originally Posted by drkeng

just curious, in my 435 on the last stretch of highway (see map below) before my exit it is possible to hit triple digits (so I'm told) and on the offramp marked with the finger one can go about 40 tops without a lot of tire squealing, but the car feels stable. I think the "recommended" speed limit is 25, but those are yellow signs, highly conservative, geared to minivans and the like

what could I expect in an M4? I would think 40-45 on the offramp wouldn't be a problem. I actually think I did it many moons ago in an E46 M3 w/ SMG.
we see posts of people taking their new M's on the autobahn at triple digit speeds without complaints or problems. and, of course, many track their cars. so what's up with all the talk of instability?

The Autobahn has smooth roads.

The stock suspension has great compression tuning (which shines on smooth roads), it's the rebound tuning (which is the reaction of the shocks being upset from bad roads, i.e. dips, broken pavement, elevation changes, etc.) that causes the instability.

Whether the rear-end is upset from heavy braking or upset mid-corner, the stock shocks does not keep the rear-end controlled and stable.

[OF Hero]

OP, what did the dealership say?

[chris719]

Originally Posted by TRZ06

It's the stock rebound tuning on the shocks.

After adding coil-overs all (and I do mean ALL) the rear-end nastiness is gone.

You went to the Ohlins R/T? How does it ride compared to stock?

[SenorFunkyPants]

Originally Posted by CanAutM3

Before the camber plates, I had everything put to the OEM nominal setting. After the camber plates, I went with -2.5 front and -1.6 rear camber with all other parameters to OEM specs.

Do you have the standard toe settings for the F82 M3?
It feels like the front of mine is toeing out....it seems very eager to turn in.

[TRZ06]

Originally Posted by chris719

You went to the Ohlins R/T? How does it ride compared to stock?

At first, pretty bouncy and harsh over the bigger dips in the road.

After going with a lower spring rate in the rear and removing some pre-tension off the front spring, it's much improved.

The damping is AWESOME, it recomposes after being upset like RIGHT NOW!!!

I might play with further lowering spring rates a few mths down the road, but for now I have other things do to first.

I have it aligned with pretty much stock settings and did a corner balance and the car is very neutral in the corners, with just a tad oversteer if provoked. Excellent turn-in and balance in the corners.

What I learned in this process is proper set-up and having someone who knows what they are doing with proper equipment is key.

This is a quality kit, but it needs to be setup right. I unfortunately ended up paying a lot more in the end by having to have things fixed and changed after the fact because of poor install and set-up.

[CanAutM3]

Originally Posted by SenorFunkyPants

Do you have the standard toe settings for the F82 M3?
It feels like the front of mine is toeing out....it seems very eager to turn in.

Yes, I kept the toe to nominal OE settings.

[SenorFunkyPants]

Originally Posted by CanAutM3

Yes, I kept the toe to nominal OE settings.

Thanks...can you tell me what they are?

[suprajjang]

Originally Posted by mm767cap

I think you might be on to something here. I entered a long corner last night, relaxed the throttle, got my understeer. Mid-corner turned off DSC and tried the same move. Understeer largely gone.

Will definitely report this to my SA. Thanks for the all the feedback here guys!

Finally got a chance to read through this thread since my last post and like you, after reading about DSC and turning it off, the twitch and car feeling unsettled has gone away. Took the same off ramp 4 different times messing with the settings and turning dsc off has resolved the issue for me.