Time to unleash

q96169we said:
In a short summary, the car is way better than me so never reached the car's limit

Genuine questions now,

What speed did you manage?

Did you feel it still had much to go, as in was it still pulling hard?

How did you feel overall about the handling while pushing it?

Could you feel the LSD doing it’s job?

Cheers

Andy
 
ori said:
I’m always worries about stone chips on the track

Ori, I honestly think be picked up more stone-chips on the NC500 than I have combined on other cars. I’m sure PVR had to get the front of his 911 painted after doing the NC500 too.

I’m now just taking that as part and parcel of doing things like this :lol: so get the super fast blue one to the next one and book chips away, or similar, for the Monday morning :poke:
 
[ref]Argyll Andy[/ref], answers for you below:
What speed did you manage?
--Top speed at the end of straight is about 120-130mph, still more to go but I drove conservatively so lift off earlier than the braking point
Did you feel it still had much to go, as in was it still pulling hard?
--Car was still pulling hard until I lift off. 155mph is an easy job for the car.
How did you feel overall about the handling while pushing it?
--First of all, all the points below assuming the car is for trackday fun instead of racing.
--Overall, the car is way more capable than me.
--Chassis stiffness is amazing for an open top. TBH, you can't feel it as an open top. Way better than the F33 4 series convertable I had before.
--CoG feels very low, suspension in Sport mode gives enough support. As you can see from the photo, the car is almost flat in the corner.
--Brake never let me down despite some vibration after 10+laps. I was told this is normal for almost all oem pad. Even full M car has this issue with oem pad.
--Previously, there were some discussion about m40i being front heavy than 4 pot version. Well, I haven't driven 4 pot G29 so can't comment on the feeling. But I don't think this is an issue.
--Steering is accurate and you can do some micro adjustment during cornering and the car will listen to you. However, many car media reviewers commented that the steering feel is worse than boxter. Well, this is true. It only sends you the necessary information.
Could you feel the LSD doing it’s job?
--Yes, can feel that clearly. It's necessary to put down the power from the B58 when exiting corner. IMO, 20i may not need this. 30i is kind of on the limit of not having this. 40i will certainly need this. However, this also generates some concerns. The way it works is the same between our car and full M car. However, the full M car has the fins on the diff body to help with the cooling whereas our car doesn't. Also, the fluid temp is estimated by the control unit instead of measured by sensor, I am concerning that it may overheat. So, if I keep my plan of doing 3-5 trackday per years, I will look into the cooling a bit further and also change the diff oil every year.
 
q96169we said:
[ref]Argyll Andy[/ref], answers for you below:
What speed did you manage?
--Top speed at the end of straight is about 120-130mph, still more to go but I drove conservatively so lift off earlier than the braking point
Did you feel it still had much to go, as in was it still pulling hard?
--Car was still pulling hard until I lift off. 155mph is an easy job for the car.
How did you feel overall about the handling while pushing it?
--First of all, all the points below assuming the car is for trackday fun instead of racing.
--Overall, the car is way more capable than me.
--Chassis stiffness is amazing for an open top. TBH, you can't feel it as an open top. Way better than the F33 4 series convertable I had before.
--CoG feels very low, suspension in Sport mode gives enough support. As you can see from the photo, the car is almost flat in the corner.
--Brake never let me down despite some vibration after 10+laps. I was told this is normal for almost all oem pad. Even full M car has this issue with oem pad.
--Previously, there were some discussion about m40i being front heavy than 4 pot version. Well, I haven't driven 4 pot G29 so can't comment on the feeling. But I don't think this is an issue.
--Steering is accurate and you can do some micro adjustment during cornering and the car will listen to you. However, many car media reviewers commented that the steering feel is worse than boxter. Well, this is true. It only sends you the necessary information.
Could you feel the LSD doing it’s job?
--Yes, can feel that clearly. It's necessary to put down the power from the B58 when exiting corner. IMO, 20i may not need this. 30i is kind of on the limit of not having this. 40i will certainly need this. However, this also generates some concerns. The way it works is the same between our car and full M car. However, the full M car has the fins on the diff body to help with the cooling whereas our car doesn't. Also, the fluid temp is estimated by the control unit instead of measured by sensor, I am concerning that it may overheat. So, if I keep my plan of doing 3-5 trackday per years, I will look into the cooling a bit further and also change the diff oil every year.

Thanks for your detailed answers :thumbsup:

Confirms a lot of my thoughts just you had the freedom to explore them and a prolonged period to,assess over.

A recurring comment I get on forum runs from people travelling behind me is how flat it sits, especially cornering, and how well it puts the power down coming out of corners.

I love mine and am glad you’re enjoying yours too :driving:
 
Argyll Andy said:
Could you feel the LSD doing it’s job?
Andy
This is the first car I've owned equipped with an LSD, it's has a very weird feeling as it swaps torque from one side to the other, it feels like fishtailing but without the movement. Well I'm assuming that what it is :D

[ref]q96169we[/ref], Did you get track insurance from the circuit and how much did it cost (if you don't mind me asking)? I'm sure slotted/drilled disc's would be better on the front with some decent pads, for road they're fine and the brakes are so much better than I've had previously excepting the SL
 
[ref]sars[/ref], LSD in G29 is not torque vectoring LSD so it can't actively send torque from one side to the other side. The most it can do is to lock up the diff instead of actively sending power to the outside wheel. The feeling you described is more likely to be the inner wheel slipping at the same speed as the outer wheel when the diff is locked up under heavy acceleration.

About the insurance, I was thinking about getting one but not at the end. Price-wise, quote to cover £40k is about £300 with about £5k excess for a single trackday. If you go for multi-trackday policy, it's averaged about £250 per day. Or, if I want to cover £10k, it's about £130 with about £1k excess. I got quote from Moris and Grove&Dean. You can get quote on their website as well. Some UTbers use Adrian Flux but you need to call them to get quote. Just make sure you read the policy in detail.

Slotted or drilled disc can be better as they can clean the brake dust off from the disc and pad contacting surface so potentially reducing glazing. However, the original disc hold up really well. It's the pad material "glazing" the disc surface leading to the vibration. I think if I just occasionally do a trackday for some fun, the origianl m sport brake system is adequate. I may get a set of racing pad to be put on before the section and swap back after the section. But at the moment, I feel it's a bit too much work to do. :rofl:
 
[ref]q96169we[/ref], indeed it isn’t torque vectoring, however all conventional LSD’s transmit and control torque to each driven wheel and allow some slip and by the very nature some torque is lost during the slip. A conventional open differential allows torque to only one wheel at a time, whereas a locking differential supplies equal torque to all driven wheels. What I believe I can feel is the allowable slip of the differential from one side to the other as the wheel with the most grip gains torque and it feels like a turning moment.
 
sars said:
[ref]q96169we[/ref], indeed it isn’t torque vectoring, however all conventional LSD’s transmit and control torque to each driven wheel and allow some slip and by the very nature some torque is lost during the slip. A conventional open differential allows torque to only one wheel at a time, whereas a locking differential supplies equal torque to all driven wheels. What I believe I can feel is the allowable slip of the differential from one side to the other as the wheel with the most grip gains torque and it feels like a turning moment.

Correct , exactly same effect with a Quaife LSD, as you describe to-yo as you boot it with limited grip….

BMW tech manual says so :thumbsup:
 

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sars said:
[ref]q96169we[/ref], indeed it isn’t torque vectoring, however all conventional LSD’s transmit and control torque to each driven wheel and allow some slip and by the very nature some torque is lost during the slip. A conventional open differential allows torque to only one wheel at a time, whereas a locking differential supplies equal torque to all driven wheels. What I believe I can feel is the allowable slip of the differential from one side to the other as the wheel with the most grip gains torque and it feels like a turning moment.

I think we are talking the same thing. As said in the training materials attached by [ref]B21[/ref], we are describing the accelerated cornering scenario. Basically, the diff is locked in that scenario and the wheel speed difference is balanced via periodically slipping the inner wheel. While the slipping happens, the torque is transmitted to outside wheel which also generates extra turning force. I personally think this feels differently compared to torque vectoring so that’s why I said it’s not torque vectoring LSD.

About the extra turning force, it can be felt but not intrusive. Either because I didn’t accelerate hard enough, or the muted steering feedback hides that very well. Maybe both.
 
[ref]B21[/ref], I was looking for that kind of thing to explain it, all I could find was the information on the MSport active limited slip differential which is obviously the same thing as the MSport differential which is option code 2T4, thanks and it’s clever stuff too :thumbsup:
[ref]q96169we[/ref], I’ve not felt it during a bend, rather as I accelerate hard away from turning left or right from a junction, anyhoo it’s a very peculiar feeling and one that I don’t particularly like either. There’s an automatic response as my bottom asks to steer into the motion and my brain saying it’s not real.
 
I think I know what you meant about the feeling. It's sort of like the car think you want to "deliberate oversteering" so it put the rear diff lock into the oversteering mode as in B21's attached page.

If you want those docs, I can send it to you. Just pm your email as it seems this forum does not allow me to attach those files. I believe I downloaded them from another U.S bmw forum. So I think google G29 technical training will lead you there.
 
sars said:
[ref]B21[/ref], I was looking for that kind of thing to explain it, all I could find was the information on the MSport active limited slip differential which is obviously the same thing as the MSport differential which is option code 2T4, thanks and it’s clever stuff too :thumbsup:
[ref]q96169we[/ref], I’ve not felt it during a bend, rather as I accelerate hard away from turning left or right from a junction, anyhoo it’s a very peculiar feeling and one that I don’t particularly like either. There’s an automatic response as my bottom asks to steer into the motion and my brain saying it’s not real.


I’ve got a library of about 100 BMW training documents I’ve amassed…sometimes because they are released early there are updates that come in later..for example on the E89 initial training it said the roof could only be operated when stationary but still overall a great source of info along with TIS.

The little 20i didn’t have enough torque to really push the Quaife / tyres in most circumstances but the re-mapped 35is with 650nm certainly is making the Quaife work hard on these winter roads.

So yes I’d coined the phrase yo-yo to myself before you annunciated the same feeling / description. As you say it feels like it’s ‘going to go’ one way then another with a 2-3 second period but never develops beyond what feels like an initial acceleration than reverses..
 
[ref]B21[/ref], Would you mind sharing the 100 training docs in your library? If you are happy to share, I can pm you the link to access my home server and you can upload there directly.
 
q96169we said:
[ref]B21[/ref], Would you mind sharing the 100 training docs in your library? If you are happy to share, I can pm you the link to access my home server and you can upload there directly.

Sure no problem👌
 
B21 said:
q96169we said:
[ref]B21[/ref], Would you mind sharing the 100 training docs in your library? If you are happy to share, I can pm you the link to access my home server and you can upload there directly.

Sure no problem👌

Thanks. PM'ed you the detail.
I got the G29 and some G30 tech training materials. But not comperhensive. Also, quite interested in reading these materials even if it's not for my car. :rofl: :rofl:
 
Great thread. Really interesting.
Have considered a bit of track fun but always been a bit too scared and hear horror stories about brakes and tyres and warranty issues etc. :?

Did you do anything special ahead of just turning up and driving?

I’d also be petrified of marks and chips. You said you got some marble marks? (Is that from rubber on the track? What do they look like and are they easy to get out?
 
[ref]Sladester100[/ref], can’t comment about the warranty and hope I can never comment on this. But in general, I’m not crazy on track and didn’t operate the car outside the designed window, so it shouldn’t cause any issue other than faster wear and tear to things like brake and tyre. Even if some non wear and tear issue appears afterwards, it shouldn’t void the warranty. Only my thought though. :tumbleweed:

Two weeks before the track day, I did an oil and filter change myself as the car completed running in 2k miles ago. I went for 5w30 oil instead of 0w20 from factory. Only reason is that there isn’t any good 0w20 LL17FE+ oil on the market at the moment. Potentially, thicker oil works slightly better under heavy load. Then, the day before the track day, I check tyre pressure, coolant level etc. and torque the wheel bolts to 140NM. No further thing had been done.

My car is black so the mark left by marble isn’t that visible. I only noticed this next day when I detailing the car. Very easy to remove with some BH cleanser fluid. But again, I’m not crazy on track so always tried to keep some distance to the car in the front. Maybe that’s why I didn’t pickup a lot stone chip.

Your car is the first edition so it’s the Matt Orange. I think it would be better to have some ppf to protect the Matt finish. I was thinking about having ppf applied and asked for quote from multiple places. But I’ve already had one or two stone chips on the day of taking delivery and drove back to Sheffield from Cambridge. So don’t really bother since.
 
One thing I was suprised by our car but no one asked so far is the car's drivetrain temperature management. In my previous experience, after several laps on the track, the engine oil temp, coolant temp, and gearbox temp will increase dramatically (20-40 degree more than normal operating temperature). I was expecting similar this time. But during the day, I used the BimmerLink to show some data and the engine coolant, oil, and gearbox oil temperature were always well controlled at around 95, 100, and 85 degree respectively even after 15+ laps stint, which was a big suprise to me.
 
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