Sebring Turn 17
#1
Burning Brakes
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Sebring Turn 17
So many options to take that turn... Questions- which way do you take turn 17? How much time does it take from your first braking point from back straight to full throttle out turn 17?
#2
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Dive for the wall and try to hit corner worker. As for time it is to great a variable to mean anything unless you quantify it at a minimum by car and tire. In my M3 I turn in flat on Rcomps and brake around the corner worker. On the GT3 on street tires I brush the brakes and turn in brake before corner worker. I also suck in the entry to 17 as I overslow but I do get a good exit.
Peter
Peter
#3
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On the latter, way better to practice your methodology, than the alternative...
There is a cone trapped between the expanded metal fence and the concrete jersey barrier on the overpass. You should be centerline justified on that and exactly perpendicular to the bridge, which is beyond 90 degrees from entry. Knowing this helps you DO something, rather than just bounce around waiting...
I have spent days with drivers on T17 alone, but the amount of time to be harvested there makes it all worthwhile...
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Approximate, estimated from a few videos I took a second to look at...
From start of braking (more than .3g negative, longG) to
A) head under the driveover bridge (split 1) and
B) head under the pedestrian bridge (total)
The total is much better than guessing point of WOT because a) we don't have that info on some videos and b) it all works out by the end point! If WOT is sooner, the second split of the total segment will be better.
Cory F 2006 996 GT3RS 2:08.7 6.9, 12.4
Sean Johnson 2011 ALMS Winter Test 997 GT3 Cup GTC, 2:10 6.8, 12.6
Clarke/Sly last week 996 Cup 2:16.9 7.6, 13.7
TRAKCAR 2011 Winterfest 2:19.9 7.9, 13.9
Juan Lopez-Santini 2-liter 901 2:25.5 8.1, 14.3
Rad 2011 Winterfest FIAT 2:21.7 9.3, 15.8
and 2-liter sports car 2:05.4 6.4, 11.5
A LOT can be learned from this study...
From start of braking (more than .3g negative, longG) to
A) head under the driveover bridge (split 1) and
B) head under the pedestrian bridge (total)
The total is much better than guessing point of WOT because a) we don't have that info on some videos and b) it all works out by the end point! If WOT is sooner, the second split of the total segment will be better.
Cory F 2006 996 GT3RS 2:08.7 6.9, 12.4
Sean Johnson 2011 ALMS Winter Test 997 GT3 Cup GTC, 2:10 6.8, 12.6
Clarke/Sly last week 996 Cup 2:16.9 7.6, 13.7
TRAKCAR 2011 Winterfest 2:19.9 7.9, 13.9
Juan Lopez-Santini 2-liter 901 2:25.5 8.1, 14.3
Rad 2011 Winterfest FIAT 2:21.7 9.3, 15.8
and 2-liter sports car 2:05.4 6.4, 11.5
A LOT can be learned from this study...
#6
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On the former, good advice. The worker often raises the rear door of her Taurus wagon, which you can see above the wall. At that point, you should be able to reach out of the passenger side window and touch the wall...
On the latter, way better to practice your methodology, than the alternative...
There is a cone trapped between the expanded metal fence and the concrete jersey barrier on the overpass. You should be centerline justified on that and exactly perpendicular to the bridge, which is beyond 90 degrees from entry. Knowing this helps you DO something, rather than just bounce around waiting...
I have spent days with drivers on T17 alone, but the amount of time to be harvested there makes it all worthwhile...
On the latter, way better to practice your methodology, than the alternative...
There is a cone trapped between the expanded metal fence and the concrete jersey barrier on the overpass. You should be centerline justified on that and exactly perpendicular to the bridge, which is beyond 90 degrees from entry. Knowing this helps you DO something, rather than just bounce around waiting...
I have spent days with drivers on T17 alone, but the amount of time to be harvested there makes it all worthwhile...
Didn't know about the cone but my coach last weekend was working on getting me rotated farther at that point so I could get on the power sooner and safer track out. Will look for the cone during Winterfest.
Peter
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Because the severity of the reaction of the car to the bumps varies according to speed, mass, cornering loads and heading, I try my best to avoid the two worst ones, those closest to the right side wall on the entry side, slightly before going under the bridge.
Bobby Rahal, Bruce MacInnes and I had extensive discussions about it and we all agreed that an incoming tangent that allows what 85Gold was trying to do (shorten and advance the rotation period, before going under the bridge, perpendicular to it) lessened the lateral "skipping" that invariably occurred taking just about ANY line through Sunset Bend (T17).
You just have to realize that like exiting T1, going through T10 and T13 (Tower Turn), continual passage at adequate speed through T17 will EVENTUALLY make you **** blood and break the car!
Bobby Rahal, Bruce MacInnes and I had extensive discussions about it and we all agreed that an incoming tangent that allows what 85Gold was trying to do (shorten and advance the rotation period, before going under the bridge, perpendicular to it) lessened the lateral "skipping" that invariably occurred taking just about ANY line through Sunset Bend (T17).
You just have to realize that like exiting T1, going through T10 and T13 (Tower Turn), continual passage at adequate speed through T17 will EVENTUALLY make you **** blood and break the car!
#10
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I tried a few things on my own.
a) get as close to the corner worker as possible.
b) Aim for the cone on the bridge as you described, at this point I am off the brake and off the throttle trying to just carry the speed in.
c) "the final part" just as you passing the cone on the bridge is the most inconsistent place for me right now. The car is bouncing a lot, and I can't have an exact point to start back on throttle. "I think" I may be waiting too long to get back on throttle.
a) get as close to the corner worker as possible.
b) Aim for the cone on the bridge as you described, at this point I am off the brake and off the throttle trying to just carry the speed in.
c) "the final part" just as you passing the cone on the bridge is the most inconsistent place for me right now. The car is bouncing a lot, and I can't have an exact point to start back on throttle. "I think" I may be waiting too long to get back on throttle.
#11
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Get rotated and back on the power just before the bridge (if not compromised because of traffic).
#13
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I aim for the corner worker and am off the brake and on the throttle probably 50 ft before the bridge, aiming to pass under that cone that Peter described. Slight throttle as I let off the brake, increasing gradually to full throttle as I pass under the bridge. When I work with a pro coach, I usually get on the throttle sooner than when I drive alone. Tough turn.
#14
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The key to 17--regardless of "line"--is getting the majority of rotation done BEFORE the bridge...
#15
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I tried a few things on my own.
a) get as close to the corner worker as possible.
b) Aim for the cone on the bridge as you described, at this point I am off the brake and off the throttle trying to just carry the speed in.
c) "the final part" just as you passing the cone on the bridge is the most inconsistent place for me right now. The car is bouncing a lot, and I can't have an exact point to start back on throttle. "I think" I may be waiting too long to get back on throttle.
a) get as close to the corner worker as possible.
b) Aim for the cone on the bridge as you described, at this point I am off the brake and off the throttle trying to just carry the speed in.
c) "the final part" just as you passing the cone on the bridge is the most inconsistent place for me right now. The car is bouncing a lot, and I can't have an exact point to start back on throttle. "I think" I may be waiting too long to get back on throttle.
b) if you're off the brake and off the throttle AND TURNING, you're slowing down. That is what the brakes are for. You may be aiming at the cone at too shallow an angle, which is causing you to turn too early and turn for too long which causes c)
c) if you THINK you're waiting too long to return to throttle, you definitely are!
Try and reduce the amount of time it takes, hence the distance you cover, to get the car rotated and pointed at the cone. You may need to head left more, finish the braking, TURN the car towards the cone FIRST, then positively get on the power. This allows you to be opening the wheel over the worst bumps instead of holding a steady arc and prolonging the agony.
I aim for the corner worker and am off the brake and on the throttle probably 50 ft before the bridge, aiming to pass under that cone that Peter described.
Slight throttle as I let off the brake, increasing gradually to full throttle as I pass under the bridge.
When I work with a pro coach, I usually get on the throttle sooner than when I drive alone. Tough turn.
Slight throttle as I let off the brake, increasing gradually to full throttle as I pass under the bridge.
When I work with a pro coach, I usually get on the throttle sooner than when I drive alone. Tough turn.
Certainly, one of the main purposes of a coach is to help you prioritize the importance of control inputs, establish landmarks and keep these front and center in your mind. Sounds like you leverage that resource well.