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      04-15-2012, 07:29 PM   #1
ThunderMoose
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A lil spin out at Texas World Speedway

I have been tracking for about a year and a half now. For the first year (~3 events), I was driving my E92 daily driver, so traction control seemed to be very prudent. Last December I bought an E46 just for the track. Even then, I was still keeping DSC on as I learned the car. This weekend I decided it was time to ween myself off of traction control.

I ended up spinning twice in my first session with it off + some oversteering through the chicanes. It was helpful having the SoloDL as I thought I simply let off the gas through my two spins, but it appears that I was braking while turning in both cases. I avoided spins the rest of the weekend by dialing it back a bit and making absolutely sure to straight-line braking + to stay on throttle through the turns. Very humbling but good experience.


Here's a video of a few laps from my first session with DSC off. Spin is at 2:57.

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      04-15-2012, 08:00 PM   #2
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Thanks for sharing. It looks like a pretty smooth/safe off, glad you and your car are ok. I used to watch videos of spins and crashes to remind myself not to try to be a hero at the track the next day.
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      04-15-2012, 08:04 PM   #3
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Glad nothing was damaged and a lesson learned. Have to be quick with the corrections...before it gets that far out. It's all about seat time and car control. Thanks for sharing.
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      04-15-2012, 09:47 PM   #4
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looked like fun. I love tws.
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      04-15-2012, 10:02 PM   #5
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Glad you and the car are OK.

A little bit of trail braking shouldn't be a problem, I don't think this is what got you to spin.

Too much throttle too soon maybe...

During your vid, I noticed you were quite often at WOT at the apex of most turns. Remember to squeeze and unwind at track out. Anyway just my 2 cents, tough to say without actually sitting in the car.

I think this shows how much more can be learnt about car control with DSC off.

Last edited by CanAutM3; 04-16-2012 at 08:53 AM. Reason: Correct typos
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      04-16-2012, 08:44 AM   #6
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I have the same helmet!

[that's all I have]
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      04-16-2012, 07:41 PM   #7
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Quote:
Originally Posted by CanAutM3 View Post
Glad you and the car are OK.

A little bit of trail braking shouldn't be a problem, I don't think this is what got you to spin.

Too much throttle too soon maybe...

During your vid, I noticed you were quite often at WOT at the apex of most turns. Remember to squeeze and unwind at track out. Anyway just my 2 cents, tough to say without actually sitting in the car.

I think this shows how much more can be learnt about car control with DSC off.
I went back and looked at the SoloDL data a bit more, and I believe you're partially correct. Looking at my lateral G data, I was at threshold after braking while turning in, then when I started to squeeze the throttle, I see my rear wheel speed separate from my front wheel speed - I take to mean that I had finally lost grip.

The newbie line at TWS has you late apexing most turns, so you can usually be well into throttle at the APEX. However, after this session, I noticed I did a lot better of squeezing the throttle versus stomping it (with DSC on).

My logger records DSC engagement, and it typically engaged through that turn each time. So I had built up some pretty bad habits.

Quote:
Originally Posted by vonwilbs View Post
Hey ThunderMoose,

Looks like you were super slow in recognizing and catching the rotation which can easily happen in a big soft street car. Getting the car to rotate like that on turn in is the fast way to drive you just have to be ready to catch it and go. In fact what you really want is to consistently induce that rotation and anticipate catching it every time. As a serious recommendation, you should go karting. It will help you with car control and hand speed.
I agree that I was super slow. This was my first spin out so I was in a bit of "what the heck is going on" mode. Hopefully I'll do a better job of recognizing the loss of traction next time. Sad part is that this car is pretty track-ready - BBK up front, KW V3 suspension with camber plates, 275/35/18 R-comps on all corners, half-cage, racing seats, 6 pt harness - it's only lacking a track-ready driver, but I am trying. I'll try to go karting or maybe autoX to help get some quickness.
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      04-16-2012, 07:56 PM   #8
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The SoloDL records DSC engagement? Which field?

Last edited by ILLCOMM; 04-16-2012 at 08:08 PM.
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      04-16-2012, 08:19 PM   #9
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Quote:
Originally Posted by ILLCOMM View Post
The DL records DSC engagement? Which field?
It showed up as DSC_REG in RaceStudio. There are actually a bunch of channels that come in that don't show up in the literature. I think ABS engagement shows up as well.
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      04-16-2012, 08:27 PM   #10
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Quote:
Originally Posted by ThunderMoose View Post
It showed up as DSC_REG in RaceStudio. There are actually a bunch of channels that come in that don't show up in the literature. I think ABS engagement shows up as well.
It just keeps getting better! Thanks.
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      04-16-2012, 08:40 PM   #11
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Looks like a few things all in concert.

1. Turned in too soon - At 2:58 you are about to take out the curb and you are still pre-apex on that specific turn.

2. Started your turn-in under full brake - At 2:56 you can see this. Most likely this is what snapped you around due to the rear being unloaded.

3. Weight transfer - At and after 2:57 you should have been on more throttle than is registering if not full to transfer the weight to the rear and catch the back end. This also contributed to the full spin but may have not helped anyway due to item 1 and 2.


Otherwise - looks good!

I miss TWS - Need to finish my car ASAP so I can come join you!
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      04-16-2012, 08:47 PM   #12
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Quote:
Originally Posted by disapr View Post
Looks like a few things all in concert.

1. Turned in too soon - At 2:58 you are about to take out the curb and you are still pre-apex on that specific turn.

2. Started your turn-in under full brake - At 2:56 you can see this. Most likely this is what snapped you around due to the rear being unloaded.

3. Weight transfer - At and after 2:57 you should have been on more throttle than is registering if not full to transfer the weight to the rear and catch the back end. This also contributed to the full spin but may have not helped anyway due to item 1 and 2.


Otherwise - looks good!

I miss TWS - Need to finish my car ASAP so I can come join you!
Yep, yep, and yep. One thing I had to get used to with the wider stickier tires (though I won't blame them for my spin) was that turn-ins were much more responsive. If you look at the first lap through 13/14/15, I would normally have to chop the wheel from 13 to get to 14 with my PSS, but with the 275 NT01's, I needed to be a lot smoother.

One thing to note is that the BRAKE input for the E46 M3 is just a binary input, so I may not have been on full brakes, but I definitely wasn't getting any power to the back.

Look forward to seeing you out there. I am trying to sneak in 1-day at beginning of June.
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      04-16-2012, 09:07 PM   #13
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Quote:
Originally Posted by ThunderMoose View Post
I agree that I was super slow. This was my first spin out so I was in a bit of "what the heck is going on" mode. Hopefully I'll do a better job of recognizing the loss of traction next time. Sad part is that this car is pretty track-ready - BBK up front, KW V3 suspension with camber plates, 275/35/18 R-comps on all corners, half-cage, racing seats, 6 pt harness - it's only lacking a track-ready driver, but I am trying. I'll try to go karting or maybe autoX to help get some quickness.
This may be where you want to take a step back. Going to Rcomps without a good toolbox full of car control is a recipe for the car surprising you. It's big of you to be open to criticism.
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      04-16-2012, 09:12 PM   #14
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Oh, and get a Hans before you go on track again!!!
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      04-16-2012, 09:35 PM   #15
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Quote:
Originally Posted by disapr View Post
Looks like a few things all in concert.

1. Turned in too soon - At 2:58 you are about to take out the curb and you are still pre-apex on that specific turn.

2. Started your turn-in under full brake - At 2:56 you can see this. Most likely this is what snapped you around due to the rear being unloaded.

3. Weight transfer - At and after 2:57 you should have been on more throttle than is registering if not full to transfer the weight to the rear and catch the back end. This also contributed to the full spin but may have not helped anyway due to item 1 and 2.
Not sure about this. My take:

1. At 2:58 the car is pointing towards the curb because it has already started to oversteer (notice how it is not traveling towards the curb even if it is pointing at the curb).


2. The car did not seem to have started to over rotate while the brakes where applied.

3. I think getting too hard on the throttle too early is what got the car to over rotate by loosing rear traction. More throttle would have just made things worse. But I agree, once the over rotation started, getting off the throttle entirely led to the actual spin. Modulating the throttle while counter steering would have yielded a wonderful smoky drift .

Last edited by CanAutM3; 04-17-2012 at 08:28 AM.
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      04-16-2012, 09:52 PM   #16
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Quote:
Originally Posted by ThunderMoose View Post
Yep, yep, and yep. One thing I had to get used to with the wider stickier tires (though I won't blame them for my spin) was that turn-ins were much more responsive. If you look at the first lap through 13/14/15, I would normally have to chop the wheel from 13 to get to 14 with my PSS, but with the 275 NT01's, I needed to be a lot smoother.

One thing to note is that the BRAKE input for the E46 M3 is just a binary input, so I may not have been on full brakes, but I definitely wasn't getting any power to the back.
It is true that the technique being taught to newer drivers is to brake in a straight line, keep moderate and steady throttle from turn-in to apex (constant speed) and squeeze the throttle while unwinding the steering to track out. While it is safer and easier to execute, it is not necessarily the fastest way around a corner. The fastest way around a corner (most corners that is) is to slow down all the way to the apex and then accelerate from there (just watch data loggers from pro-drivers). So trail braking is perfectly OK (requires experience and practice though).

If you can accelerate before you got to the apex, it only means you entered a corner too slow. IMO, this is probably the habit that got you in trouble. When your speeds were slower, you could get away with it. Now that you are much faster, getting on the throttle too early pushes you out of the friction circle.

This is something I always keep repeating to my students: wait, wait, wait for the apex before accelerating.

BTW, hats off to you for accepting input, it is the best way to learn and to form your own opinion.

Last edited by CanAutM3; 04-16-2012 at 10:32 PM.
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      04-16-2012, 11:06 PM   #17
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glad that you're alright and the car is ok. I'm no expert, so track veterans please correct if I'm wrong here, but one thing I've learned from the last couple seasons of track driving is that you need to be brave with the throttle. once you turn in and apply some 'maintenance' throttle, you have to stay committed to it - if you look at the throttle bar in your nifty track camera setup, you can see what happens. you go from applying throttle as you turn in (although a bit much) to a slight oversteer, which is then made even worse by completely lifting off the throttle (see 2:58). when you lift off the throttle like that, the weight of the car shifts forward, further reducing the traction at the rear and causing it to come around even more.

learning to be brave with the throttle and staying committed once you turn in takes experience, and it's difficult and very dangerous to learn at high speeds since you're not always blessed with such a nice run-off on both sides as you had in this case - autocross is a great place to learn.

props to you for posting a great video and keeping your humility about it
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      04-16-2012, 11:33 PM   #18
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Quote:
Originally Posted by ThunderMoose View Post
Yep, yep, and yep. One thing I had to get used to with the wider stickier tires (though I won't blame them for my spin) was that turn-ins were much more responsive. If you look at the first lap through 13/14/15, I would normally have to chop the wheel from 13 to get to 14 with my PSS, but with the 275 NT01's, I needed to be a lot smoother.

One thing to note is that the BRAKE input for the E46 M3 is just a binary input, so I may not have been on full brakes, but I definitely wasn't getting any power to the back.

Look forward to seeing you out there. I am trying to sneak in 1-day at beginning of June.
Nice even slide off the track though, good job with that one.

I completely agree with you - I went into more technical detail of what I assumed happened - but ultimately - it appears that you had enough traction for less steering input. It's actually nice that the car turned in that well.
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      04-17-2012, 05:36 AM   #19
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Quote:
Originally Posted by Car54 View Post
This may be where you want to take a step back. Going to Rcomps without a good toolbox full of car control is a recipe for the car surprising you. It's big of you to be open to criticism.
Agreed, I wasn't really wanting to put them on yet, but when I was doing a test fitment after getting my front camber plates installed, I found a large screw in my front wheel of my street tires.

I'll post a video of my second day session. I think I made some good improvement overall, but I still need some more car control experience.
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      04-17-2012, 07:39 AM   #20
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Quote:
Originally Posted by CanAutM3 View Post
It is true that the technique being taught to newer drivers is to brake in a straight line, keep moderate and steady throttle from turn-in to apex (constant speed) and squeeze the throttle while unwinding the steering to track out. While it is safer and easier to execute, it is not necessarily the fastest way around a corner. The fastest way around a corner (most corners that is) is to slow down all the way to the apex and then accelerate from there (just watch data loggers from pro-drivers). So trail braking is perfectly OK (requires experience and practice though).

If you can accelerate before you got to the apex, it only means you entered a corner too slow. IMO, this is probably the habit that got you in trouble. When your speeds were slower, you could get away with it. Now that you are much faster, getting on the throttle too early pushes you out of the friction circle.

This is something I always keep repeating to my students: wait, wait, wait for the apex before accelerating.

BTW, hats off to you for accepting input, it is the best way to learn and to form your own opinion.
I was at a seminar on Saturday on V-boxes & video and its use in developing your driving & improving lap times.Some real interesting basic things were discused that should help me with dealing with students and instructors.I am sure I do this instictivly but forget to instill this in students.

Steer fast on slow corners to get the car pointed as straight as possible before opening the throttle.Unwinding the wheel before the throttle is opened fully.
Steer slow on fast corners.


Some really good stuff on his website and make sure you watch his video's.

http://www.nigelgreensall.com/
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      04-17-2012, 08:34 AM   #21
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Quote:
Originally Posted by CanAutM3 View Post
It is true that the technique being taught to newer drivers is to brake in a straight line, keep moderate and steady throttle from turn-in to apex (constant speed) and squeeze the throttle while unwinding the steering to track out. While it is safer and easier to execute, it is not necessarily the fastest way around a corner. The fastest way around a corner (most corners that is) is to slow down all the way to the apex and then accelerate from there (just watch data loggers from pro-drivers). So trail braking is perfectly OK (requires experience and practice though).

If you can accelerate before you got to the apex, it only means you entered a corner too slow. IMO, this is probably the habit that got you in trouble. When your speeds were slower, you could get away with it. Now that you are much faster, getting on the throttle too early pushes you out of the friction circle.
I think this really only applies to type 2 corners. I'm not sure what I'd consider the OP's issue corner...combo type 1/2 or just a 3. I think the fast way around there is to time a perfect TTO trailing throttle oversteer. I think that's what his butt was telling him to do, just had a hard time executing it. Looks like a real fun track though!
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      04-17-2012, 09:06 AM   #22
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Quote:
Originally Posted by Car54 View Post
I think this really only applies to type 2 corners. I'm not sure what I'd consider the OP's issue corner...combo type 1/2 or just a 3. I think the fast way around there is to time a perfect TTO trailing throttle oversteer. I think that's what his butt was telling him to do, just had a hard time executing it. Looks like a real fun track though!
Agreed, I did say slowing down all the way to the apex, not necessarily braking all the way to the apex .

EDIT:
You can still be slowing down while applying throttle. This is demonstrated in the videos in the link provided by Gearhead. If you watch carefully the data logger, you will notice that on the vast majority of corners he was able to take cleanly, the slowest point is the apex.

However, some turns can be taken flat out (or with a slight lift), so naturally this concept does not apply.

Last edited by CanAutM3; 04-17-2012 at 07:19 PM.
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