Oversteer or Rotation?

Shadow277

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Had a technical question. Some tight hair pins I clip I noticed that the back becomes a little loose (is this what "lively" means?) Which I don't really mind as much because I am still on the correct racing line. However, I was told from someone with way more experience than I that sliding is not fast. So if my rear becomes a little loose then that is an indication of entering the corner too fast?

Is what I am experiencing called oversteer where more speed equals a power slide or is this what Randy Pobst calls rotation?





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Had a technical question. Some tight hair pins I clip I noticed that the back becomes a little loose (is this what "lively" means?) Which I don't really mind as much because I am still on the correct racing line. However, I was told from someone with way more experience than I that sliding is not fast. So if my rear becomes a little loose then that is an indication of entering the corner too fast?

Is what I am experiencing called oversteer where more speed equals a power slide or is this what Randy Pobst calls rotation?
Sliding isn't fast, that's correct. Controlled yaw/rotation is very different from true oversteer, as it's keeping more of the "static-esque" friction between tires and the road surface, which has a higher coefficient of friction. Oversteer and understeer is asking the front or rear tires to do too much at one time. If you are seeing oversteer on the entry phase of the corner, you are probably upsetting the car via inputs (timing of brakes or lift-throttle). If it's at the exit of the corner, you're probably using too much throttle too early.

Lots of the "popular" or mainstream setups feel playful and balanced at 6-7 tenths but are far too lively near the limit to be driven quickly. People often throw too much rear bar at these cars, as an example.
 
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Shadow277

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Sliding isn't fast, that's correct. Controlled yaw/rotation is very different from true oversteer, as it's keeping more of the "static-esque" friction between tires and the road surface, which has a higher coefficient of friction. Oversteer and understeer is asking the front or rear tires to do too much at one time. If you are seeing oversteer on the entry phase of the corner, you are probably upsetting the car via inputs (timing of brakes or lift-throttle). If it's at the exit of the corner, you're probably using too much throttle too early.

Lots of the "popular" or mainstream setups feel playful and balanced at 6-7 tenths but are far too lively near the limit to be driven quickly. People often throw too much rear bar at these cars, as an example.
That makes total sense as I was new to that area. So my actual problem was weight transfer then? I think I'll need to brush up on brake zones and throttle control.
 

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That makes total sense as I was new to that area. So my actual problem was weight transfer then? I think I'll need to brush up on brake zones and throttle control.
Managing weight transfer is the name of the game, and is essentially all performance driving is outside of being on a particular line.
 

Grafanton

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Sliding is actually faster.
Understand that there is a distinction. We're not talking about the wild power-slides frequently seen on Top Gear or Ken Blocks Gymkhana with wheels spinning and clouds of tire smoke. But a well controlled 4 wheel drift. The 4-wheel drift can actually be a faster way around a corner. This is not a skill that I have in anyway mastered, but I'm getting closer every season.
The reason that sliding is faster is not an easy concept to explain, but if you can picture a standard bell curve graph, with speed along the bottom (x-axis) and available grip on the y-axis, at the very peak of the mountain is where the tire loses grip and begins to slide. Here's where it gets tricky, pick a point on the upward slope of the bell curve, before the tire has reached the point of sliding, now from that point, scribe a line at the same height to the downward slope of the belle curve. Those two point on the curve have the exact same amount of tire grip. Yes, one is sliding and one is not, but the overall grip is the same. The difference is, the huge amount of area under the curve and thereby speed that you've gained.
One way that I've been exploring this is with a cheaper, more durable, lower grip tire. I'm sliding much earlier than I used to with a grippier tire but I continue to gain lap time.
 
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Shadow277

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Sliding is actually faster.
Understand that there is a distinction. We're not talking about the wild power-slides frequently seen on Top Gear or Ken Blocks Gymkhana with wheels spinning and clouds of tire smoke. But a well controlled 4 wheel drift. The 4-wheel drift can actually be a faster way around a corner. This is not a skill that I have in anyway mastered, but I'm getting closer every season.
The reason that sliding is faster is not an easy concept to explain, but if you can picture a standard bell curve graph, with speed along the bottom (x-axis) and available grip on the y-axis, at the very peak of the mountain is where the tire loses grip and begins to slide. Here's where it gets tricky, pick a point on the upward slope of the bell curve, before the tire has reached the point of sliding, now from that point, scribe a line at the same height to the downward slope of the belle curve. Those two point on the curve have the exact same amount of tire grip. Yes, one is sliding and one is not, but the overall grip is the same. The difference is, the huge amount of area under the curve and thereby speed that you've gained.
One way that I've been exploring this is with a cheaper, more durable, lower grip tire. I'm sliding much earlier than I used to with a grippier tire but I continue to gain lap time.
You make total sense. So I should ditch the Firehawks and go with some all seasons?
 

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Sliding is actually faster.
Understand that there is a distinction. We're not talking about the wild power-slides frequently seen on Top Gear or Ken Blocks Gymkhana with wheels spinning and clouds of tire smoke. But a well controlled 4 wheel drift. The 4-wheel drift can actually be a faster way around a corner. This is not a skill that I have in anyway mastered, but I'm getting closer every season.
The reason that sliding is faster is not an easy concept to explain, but if you can picture a standard bell curve graph, with speed along the bottom (x-axis) and available grip on the y-axis, at the very peak of the mountain is where the tire loses grip and begins to slide. Here's where it gets tricky, pick a point on the upward slope of the bell curve, before the tire has reached the point of sliding, now from that point, scribe a line at the same height to the downward slope of the belle curve. Those two point on the curve have the exact same amount of tire grip. Yes, one is sliding and one is not, but the overall grip is the same. The difference is, the huge amount of area under the curve and thereby speed that you've gained.
One way that I've been exploring this is with a cheaper, more durable, lower grip tire. I'm sliding much earlier than I used to with a grippier tire but I continue to gain lap time.
The X axis and the graph you're talking about isn't speed, but slip angle, which can be mutually exclusive from speed.
 

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You make total sense. So I should ditch the Firehawks and go with some all seasons?
Your point is well taken and maybe I mis-stated how this is working for me. I am exploring car control. At some point I hope to change to a grippier tire, but still maintain the same car control and dynamics, that's where I'll find real speed.
 

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It took one trip around the track as a passenger with a good driver and I understood what rotation felt like.
 
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It took one trip around the track as a passenger with a good driver and I understood what rotation felt like.
I need that experience. Exotics Racing is fun and all, but I feel like I could do way better. I keep telling myself that there might not be much more theoritics for me to learn. I'm a nerd. Watched a lot of Randy Pobst on Youtube, racing sims for years, etc. It all comes down to more seat time. There's a reason pilots must fly so many hours a year or else they lose their license. Perhaps it is the same concept for us.
 

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Lots of the "popular" or mainstream setups feel playful and balanced at 6-7 tenths but are far too lively near the limit to be driven quickly. People often throw too much rear bar at these cars, as an example.
I’m interested in your opinion Brian what is too much rear bar on these cars? I know driving style has an impact but I’ve been thinking lately that my gt350r rear bar may be too much. I put both oem gt350r bars on my Ecoboost and like you said around town it’s great. But anything under 50mph on track and I can’t put power down nearly as early as I feel I should be able to. It’s like a drift event.
 

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I’m interested in your opinion Brian what is too much rear bar on these cars? I know driving style has an impact but I’ve been thinking lately that my gt350r rear bar may be too much. I put both oem gt350r bars on my Ecoboost and like you said around town it’s great. But anything under 50mph on track and I can’t put power down nearly as early as I feel I should be able to. It’s like a drift event.
Yes, that's too much unless you have substantial front spring rate. Obviously that's not the only part of the setup that matters for this, but it definitely contributes significantly.

Stock GT PP/EB PP bars are a good spot to be in.
 

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