Happy Thanksgiving! Ok, Jeff, I will analyze your video over this holiday weekend. Regarding my travels to Sebring: I have several people besides yourself who would like to share me for a couple of days. The rub is getting everyone on the same page schedule-wise...plus nobody wants to be the "lead person" to put it all together
Definitely a first world problem! It will get sorted out

 

OK, Jeff, that was a pretty tidy lap! Nice and controlled, nothing out of control or off track. Well done. My commentary below relates to small details, but as you know, at Sebring (like at the Glen this past summer for us), these little things can translate into big changes in our lap times, when executed well. I do strongly believe you should move your Clubsport gear lever to the left after putting it in Drive, and choose your gears yourself, particularly here at Sebring. The PDK is often putting you in a suboptimal gear in this video. This will be clear in my commentary & observations below. Noter that nothing you are doing is bad, etc. I am just pointing out opportunities for sizable improvement without putting you more in harm's way:

T1: This is a 4th gear corner. Doing it in 3rd isn't helping, and in fact it is hurting you. Why? Because as you coast up until the point at which you go to strong throttle, engine braking is really slowing the car well below its potential. You have a very good line here, and after turning in, front tire scrub will continue to slow the car until you get back on gas. But the high RPM's of 3rd gear are also killing speed unnecessarily. Watch your MPH in here: as you approach the inner wall, you are at ~89 MPH. Speed drops top 80 MPH quickly, though. Now, this is a very nice vMin. However, your potential and the potential of your car, particularly as stable as it looks here, it notably higher than that. T1 is physically huge, and this really impacts lap times. Also, in an ideal world, you'd bet on notable positive throttle at 0:15, rolling to WOT at 0:16, versus 0:20 as you are doing here. That would mean 4 extra seconds of full power here! And you would carry that all the way to T3. Big effect on segment & lap time IMO.

T3: This is a 3rd gear corner! 2nd buys you nothing, and PDK is upshifting anyway just past apex. Also, IMO, you would really benefit with more trail braking here. You jump off the brakes at 0:26. Trail braking maybe another 5' or so will move your brake zone deeper into the corner, help the car turn better, & allow you to get back on power sooner coming out.

T5: IMO you are braking early (at 0:31), unnecessarily so. Instead, brake closer to 0:33 and trail brake lightly to help the car rotate better & enable more throttle sooner. In fact, this would enable you to use way more throttle at 0:34, and WOT at 0:35. You would carry this advantage all the way to T7! Such a long straightaway, imagine what that will do to segment/lap time

T7: Nice job with early throttle on exit! However, IMO you need to trail brake a lot more here. You jump off the brakes at 0:53. This causes the nose of the car to lift, shrinking the front contact patches just when you need them most. As a result, you push partially wide of the apex curbing, and only use part of it. Getting all the way in via trail braking will enable you to use all of the curb, which will then enable you to straighten steering sooner = more exit speed. Again, you would carry this MPH advantage all the way to T10 = huge segment/lap time gain.

T10: Also a 3rd gear corner. 2nd is not helping here. Also, again, you would benefit from trail braking. It will help the car point better & move the brake zone deeper into the corner. Instead, you jump off the brakes at 1:12. Had you been in 3rd, you could have upshifted to 4th at 1:16, which IMO would have eliminated the need for your partial lifts at 1:16 and 1:19. Again, all of this is additive to improved times.

T13: Also a 3rd gear corner, that would also benefit from trail braking a bit more. IMO this would, in an ideal world, enable you to be WOT at 1:26 versus 1:29! Considering the real estate that follows, this could again really benefit your times.

Bishops: In an ideal world, you'd be at full throttle until the T15 brake zone. One way to get there, with peace of mind, is to upshift to 5th at 1:35, and then to 6th at 1:37. This will really settle the back end down, enabling you to use a lot more throttle position for a lot more real estate. This will obviously change the brake zone into T15, but IMO this is a good problem to have.

T15: This is another place where you would benefit from trail braking a bit more. This will place the car more easily onto the apex curbing, which would allow you to be unwinding steering and at WOT at 1:44 versus 1:45. Not a huge gain, but every bit helps.

T16: You have a great entry angle here, and do a fantastic job of using all of the apex curbing!!! As such, your potential here is to be at WOT at 1:51 versus 1:53. That is 2 whole seconds of full throttle that you would carry down the longest straightaway of the track. You can do that math...

T17: Very nice vMin here. However, you get close to vMin at 2:12 and stay there until 2:17. This is hundreds and hundreds of feet at or near our vMin. Your opportunity here is to shrink the amount of real estate or near vMin. To do this, consider braking a bit more gently and downshifting more slowly. The PDK has you in 3rd gear when you are along side the corner station. There is no need for this IMO, and that engine braking (plus front tire scrub) is killing your speed from there to the bridge, just as we saw into T1. You can carry a bit more MPH a bit deeper here, and use the front tire scrub to continue slowing the car. Also, given your line, IMO you can be at WOT at 2:17 versus 2:18. Given the consequences at this corner, work up to this gradually. If we are able to be at Sebring together this winter, I will show you how to incrementally take advantage of your opportunity here, safely.

I hope all of this makes sense. Little, little things that at your level really matter!!!

 

^ Thank you Dave! Awesome of you to take the time to provide such detail. Promise to start choosing gears myself beginning next track weekend, Dec. 13-15.
I'll print out the notes above to post in the trailer for reference and get to work. Cheers.

 

Is this open to non US, non Porsche laps?

 

Yes it is! If it is a track I have never driven or coached, I will say so, and will figure the track out on my own. Then, I will still give you professional analysis.

 

Awesome, that would be much appreciated.

Video is above.
This is the circuit
https://en.wikipedia.org/wiki/Wanneroo_Raceway

 

Ok thank you. Please give me a couple of days

 

In Oz! Thirty miles north of Perth! Barbagallo, if I remember.

Worked with some vintage and historic racers from the US there. Fun track, about the same length as Lime Rock Park in the US.

 

OK, I just sent you a PM with my comments/suggestions.

 

Just wanted to bump this thread and highly recommend Dave if you ever get the chance to hire him. If not already blatantly apparent from the above, he’s very knowledgeable (in addition to being very generous with his time). I’m a very experienced driver (and coach myself), with well over 100 track days, and I compete (and usually win) in Time Trials. Dave was able to make 2-3 suggestions that I’ve been working on for a couple of months and I just lowered my already really good lap time at Sebring by .7s, and it wasn’t due simply to better weather, but to Dave’s suggestions.

For any HPDE participant that’s perhaps just gone solo, or has a good bit of experience and has hit a plateau and is spending money on brakes, tires and entry fees trying to figure it out yourself - hire a coach. You’ll learn more in one day with someone like Dave than you would by experimenting yourself over 10+ track days, so the ROI is absolutely there!

 

Thank you for the kind words, Mike! And congratulations on that significant improvement! I will look at your video later today and email you any updated comments and suggestions

 

Given all the Sebring traffic (bad pun unintended) feel free to share thoughts publicly. Reference lap in question for others is below. The delta is to my optimal lap, which was set at 10am the day before where I managed to carry a vMin of 83 in T1 vs the 81 here.

 

Will do

 

Mike, since you asked for me to share my thoughts in public, they are below, and are minor nuances which can be significant, particularly in a lower-power car like yours:

- T1: As you point out, there is a bit of opportunity here, which you exploited in the morning session. What I see here in this video, at around 0:11, is the opportunity to transition off brakes and to a very small bit of positive throttle. The objective is two-fold: to stabilize the car, and to stop the front tire scrub from continuing to kill speed. At 0:11 you are at 86 MPH, which drops to 81 MPH by 0:13, when positive throttle resumes. if there is a way to use a very small amount of positive throttle closer to 0:11 or even 0:12, you have the opportunity to be closer to 86 MPH as your vMin here, and potentially be at vMin for a bit less real estate.

- T10: At around 1:11, you turn in really smoothly, with some nice light trail braking. If, at 1:11-1:12, you were able to add just a tiny bit more steering as you apex, your exit trajectory wouldn't put you quite so far driver's left at 1:14. This would be advantageous because it would enable you to straighten the wheel sooner, and allow the car to settle more, before bending it left at 1:15. It would also require a bit less steering angle at 1:16 or so. All of this would reduce front tire scrub, resulting in a higher velocity from around 1:13 all the way to braking at 1:22, a huge chunk of real estate, particularly in a lower-power car.

- T13: Turning in a foot or two early, which puts you at a slightly early apex, which forces you to hold steering angle longer than optimal as you get to the track out curbing at 1:28. This killed a couple of MPH of exit speed, which had consequences all the way through Bishops (which you executed really well!). In a lower-power car, this is significant.

- T16: Similarly, at 1:53 you still have a significant amount of steering lock. If you were able to add a tiny bit more steering at the apex (like I mentioned above for T10), you could begin unwinding steering sooner, and thus be a lot closer to wheels-straight over that track out curb, enhancing your MPH all the way to T17

- T17: Everyone's nemesis! Solid entry, solid braking, car looked very stable. You reach your vMin at 2:13 and stay at or very close to it until 2:16. Nothing wrong with this. However, realize that, at around 65-66 MPH, you travel approximately 300 feet in 3 seconds. So you are essentially at your vMin for 300 feet. If there were a way to lower that to 200 feet, for example, there would be notable segment & lap time benefits. One way to do this is to remember how much speed that the steering angle in T17 kills, and use a bit less brake to kill MPH and a bit more more scrub. In other words, maybe brake a bit less hard, at the same spot & for the same duration...

I hope this helps!

 

Thank you - I'll work on it all and try to find another second! The good news is the first video you looked at for me my vMin in T1 was 80 and I was at vMin in T17 for 4 seconds, so I'm making progress!