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      04-21-2012, 07:22 PM   #67
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That is an ideal situation. Let's face it, how many noobs go to the track with a stock car. I started out with a heavily modded car...things have gone well. Not a one size fits all deal. I can see the issue with r-comps but starting with a good suspension? How is that bad? I will agree that an adjustable suspension might complicates things.

I think everyone criticizing the op on having a modded car is 110% missing the point. It's about your head...not the hardware. If you can't figure that one out...you need more beginner time.

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      04-21-2012, 11:20 PM   #68
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^ well said, I agree.
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      04-22-2012, 06:39 AM   #69
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Quote:
Originally Posted by Porschefile
^ well said, I agree.
Yeah, my feelings always come back.
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      04-22-2012, 07:14 AM   #70
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Quote:
Originally Posted by bigjae1976 View Post
That is an ideal situation. Let's face it, how many noobs go to the track with a stock car. I started out with a heavily modded car...things have gone well. Not a one size fits all deal. I can see the issue with r-comps but starting with a good suspension? How is that bad? I will agree that an adjustable suspension might complicates things.

I think everyone criticizing the op on having a modded car is 110% missing the point. It's about your head...not the hardware. If you can't figure that one out...you need more beginner time.

If I hurt your feelings don't worry, they regenerate.
Agree 100%. I was on R compounds by my second season of tracking and just kept modding the car and making it better. The key is to stay within your limits and add speed incrementally over time.
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      04-22-2012, 07:52 AM   #71
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I think you are all right in some way.

I am a firm beleiver that the part of the car that needs the most modification is the one between the seat and the steering wheel. So much speed can be gained by improving the driver. I always frown a little bit when I see fairly novice drivers modifying their cars to improve their lap times when they still have so much to learn. I've been tracking for 18 years and I am still learning.

That said, I don't see anything wrong with starting with a modded/track prepped car. If this is how you got it, don't un-modify it. Heck, the M3 can almost be considered as modified out of the box when compared to many cars.

My point is that you should not modify the car that you have to improve your lap times; unless you have really maxed out the abilities of the car and your ability to drive it.

Last edited by CanAutM3; 04-23-2012 at 11:44 AM. Reason: Correct typo
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      04-22-2012, 11:29 PM   #72
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Quote:
Originally Posted by ThunderMoose View Post
e-mail sent. Be gentle with me.
Alright... I looked at your data. Here's what I can see by comparing it (red) to the previous lap (blue).

You were on the throttle deeper (A) into the corner, about 50 feet deeper.

As you steered into the corner (D), you carried slightly more speed than before. As you turned your steering wheel you also braked (B/C), transferring a lot of weight onto the front axle of the car.

Finally, you stabbed on the throttle a little (E), breaking traction from the rear wheels which did not have enough traction to begin with.

You spun.

Name:  spin.png
Views: 120
Size:  257.2 KB
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      04-23-2012, 08:50 AM   #73
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Quote:
Originally Posted by Richard@M-World View Post
Alright... I looked at your data. Here's what I can see by comparing it (red) to the previous lap (blue).

You were on the throttle deeper (A) into the corner, about 50 feet deeper.

As you steered into the corner (D), you carried slightly more speed than before. As you turned your steering wheel you also braked (B/C), transferring a lot of weight onto the front axle of the car.

Finally, you stabbed on the throttle a little (E), breaking traction from the rear wheels which did not have enough traction to begin with.

You spun.

Attachment 680255
Question:

Curious to why the distances on the x-axis aren't perfectly overlaid for the two plots on the graph?

Last edited by CanAutM3; 04-23-2012 at 02:57 PM.
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      04-23-2012, 11:25 AM   #74
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Quote:
Originally Posted by Richard@M-World View Post
Alright... I looked at your data. Here's what I can see by comparing it (red) to the previous lap (blue).

You were on the throttle deeper (A) into the corner, about 50 feet deeper.

As you steered into the corner (D), you carried slightly more speed than before. As you turned your steering wheel you also braked (B/C), transferring a lot of weight onto the front axle of the car.

Finally, you stabbed on the throttle a little (E), breaking traction from the rear wheels which did not have enough traction to begin with.

You spun.
I think I understand what is going on. Would the conclusion from the data be that the correct reaction was to maintain the throttle and countersteer thus recovering from the slide?
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      04-23-2012, 11:34 AM   #75
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Quote:
Originally Posted by bigjae1976 View Post
I think I understand what is going on. Would the conclusion from the data be that the correct reaction was to maintain the throttle and countersteer thus recovering from the slide?
IMO, No.

Even after looking at the data, I still think too hard on the throttle too early with too much steering input is what started the over rotation (if you watch the video closely, you will see the RPM quickly shoot up when the throttle is applied at 2:57, indicating rear wheel spin). Lifting off completely and abruptly then caused the car to spin.

You should not get there in the first place. But if you do, the correct recovery would have been to lift off slightly while counter steering to regain rear tire grip (stop the wheel spin). Then managing the throttle to keep the car in balance.

Last edited by CanAutM3; 04-23-2012 at 04:02 PM.
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      04-23-2012, 07:27 PM   #76
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wow this is getting a lot of response.. this is good though, it's nice to work out the cause and effect.

I've driven this track many times and that particular turn is pretty fast and typically only needs a lift, if you are on line. Even in my 500RWHP blown E92 with r-comps I would only tap the brakes and dive into that turn, or lift, depending on conditions.

I've had to save it there once because I was way too hot, but, you need to be awake.
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      04-23-2012, 08:42 PM   #77
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Quote:
Originally Posted by CanAutM3 View Post
Question:

Curious to why the distances on the x-axis aren't perfectly overlaid for the two plots on the graph?
I think it's a function of the way the DL determines lap distance, which appears to be backwards. I tried to overlay the data the same way myself, but it was out of sync, since I really never made it to the stopping point before the DL reset the lap.

Quote:
Originally Posted by vonwilbs View Post
2 I still think you could have saved it and made a pretty quick corner out of it had you grabbed some counter steer when the car started to rotate and add a little throttle to settle the rear, maybe like a 2 pedal, not a 6 like you used. Hands were too slow—the real reason you couldn’t save the car.

I do have a question about your reactions though. Do you think that you added throttle because you know you aren't supposed to lift in an effort to save the car? Or do you think you were just adding throttle because you felt you were taking the turn normally?
The latter. I added throttle slightly before I started to spin. I felt that I was too hot in the corner, though I really wasn't as I have taken that turn at higher speeds. As Richard points out in the data analysis, I incorrectly tried to scrub speed (braking) while turning in - my version of chickening out. I am normally on throttle when I take that turn, so I tried to get back on throttle, but I was a bit too abrupt and without traction, which caused me to spin. If you watch my other video, to build back my confidence, I did a lot more straight line braking ahead of the turn so that I could be (confidently) on throttle through the turn to keep back end planted.
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      04-23-2012, 08:44 PM   #78
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Quote:
Originally Posted by Richard@M-World View Post
Alright... I looked at your data. Here's what I can see by comparing it (red) to the previous lap (blue).

You were on the throttle deeper (A) into the corner, about 50 feet deeper.

As you steered into the corner (D), you carried slightly more speed than before. As you turned your steering wheel you also braked (B/C), transferring a lot of weight onto the front axle of the car.

Finally, you stabbed on the throttle a little (E), breaking traction from the rear wheels which did not have enough traction to begin with.

You spun.

Attachment 680255
Thanks a bunch Richard!
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      04-23-2012, 09:09 PM   #79
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Quote:
Originally Posted by CanAutM3 View Post
Question:

Curious to why the distances on the x-axis aren't perfectly overlaid for the two plots on the graph?
I moved the x-axis of the two data sets to align the car's position on the track. The data set of the spin out lap was cut short because the car stopped and DL stopped recording.

Quote:
Originally Posted by ThunderMoose View Post
The latter. I added throttle slightly before I started to spin. I felt that I was too hot in the corner, though I really wasn't as I have taken that turn at higher speeds. As Richard points out in the data analysis, I incorrectly tried to scrub speed (braking) while turning in - my version of chickening out. I am normally on throttle when I take that turn, so I tried to get back on throttle, but I was a bit too abrupt and without traction, which caused me to spin. If you watch my other video, to build back my confidence, I did a lot more straight line braking ahead of the turn so that I could be (confidently) on throttle through the turn to keep back end planted.
Yup, hence the saying: if you are too hot in a corner, just go straight
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      04-24-2012, 08:15 PM   #80
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That is a cool analysis that must have taken time to complete...kudos!

In response to bigjae, i wasn't meaning to criticize the OP about learning on stock vs. modified car. All I was saying is from personal experience and what CanAut said is that sometimes its easier to step it up in that fashion. Do you have to? no. But I do think firm suspension cars with neutral/square setups and lots of camber are prob more than some can handle early on. Are you fast enough to catch it and set it straight? Stock cars with street tires give you TONS of feedback. heavy lean, weight transfer, you know exactly where the grip lies. The lean also teaches you how to handle that weight transfer...which is why I like autox as well. When you start feathering the outside edges of your tires on the stock car, then you know you need more camber, go a little more...and you can upgrade the suspension.

From what i have found, anytime i have upgraded the suspension on a bmw, especially from stock to full coils/camber plates...the diff is literaly superman. Nice to have the stock "lean machine" (pun intended) under your belt.

Anyway, rock on everyone.
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      04-25-2012, 01:15 AM   #81
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Quote:
Originally Posted by Modena NYC View Post
That is a cool analysis that must have taken time to complete...kudos!

In response to bigjae, i wasn't meaning to criticize the OP about learning on stock vs. modified car. All I was saying is from personal experience and what CanAut said is that sometimes its easier to step it up in that fashion. Do you have to? no. But I do think firm suspension cars with neutral/square setups and lots of camber are prob more than some can handle early on. Are you fast enough to catch it and set it straight? Stock cars with street tires give you TONS of feedback. heavy lean, weight transfer, you know exactly where the grip lies. The lean also teaches you how to handle that weight transfer...which is why I like autox as well. When you start feathering the outside edges of your tires on the stock car, then you know you need more camber, go a little more...and you can upgrade the suspension.

From what i have found, anytime i have upgraded the suspension on a bmw, especially from stock to full coils/camber plates...the diff is literaly superman. Nice to have the stock "lean machine" (pun intended) under your belt.

Anyway, rock on everyone.
I think the mods that will get people in trouble are HP upgrades, not so much suspension and brakes.

You what the worst mod for my driver's ed is so far? The damned iPhone with Harry's Lap Timer in my car. This past weekend, the sessions where I was worried about lap times and not focusing on something to work on...that session went crappy. When I focused on working on something like smooth and consistent braking...that session went well.

Then friends don't help either. Trying to chase a certain E46 M3 down and then staying in front made me super sloppy.

So no more Harry's for me right now. Going to focus on technique and worry about lap times and data when I can run a consistent line with consistent lap times.
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      04-25-2012, 09:20 PM   #82
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Quote:
Originally Posted by bigjae1976 View Post
I think the mods that will get people in trouble are HP upgrades, not so much suspension and brakes.

You what the worst mod for my driver's ed is so far? The damned iPhone with Harry's Lap Timer in my car. This past weekend, the sessions where I was worried about lap times and not focusing on something to work on...that session went crappy. When I focused on working on something like smooth and consistent braking...that session went well.

Then friends don't help either. Trying to chase a certain E46 M3 down and then staying in front made me super sloppy.

So no more Harry's for me right now. Going to focus on technique and worry about lap times and data when I can run a consistent line with consistent lap times.
You need to find a local karting league. Running with several people about your same speed on the track will help with being consistent under pressure. Just going for an arrive and drive with random people does not produce this same effect. Just my $.02.
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