Report from Sebring HPDE 4/30/11-5/1/11
 

Figured I'd post up a brief summary of how things went from my second HPDE.

Just like my first time, it was again with Chin Motorsports at Sebring. I met my instructor in the morning, who, interestingly enough, is one of the final 16 of the Nissan/Sony GT Academy. He is going to be flying over to Europe for the final competition/reality show in a week. He had a ton of competitive karting experience as well as track events in cars. Overall I thought he was a very good instructor. He does instructing normally with Sick Sideways, which were also there this weekend, so we hung out with them most of the time.

I was using Carbotech XP10/XP8 pads, with Dunlop Star Spec's 275/18's.

Saturday
So unlike my first time, where I kept the car in automatic for the first few sessions, I did the entire event in manual mode, since I felt more accustomed to the experience. I kept VDC on for Saturday, but man, it was frustrating. It's been mentioned many times before, but for the track, I just found it way too aggressive. It would come on very early, and stay way late. I would be coming out of a turn, and my tires would of been able to handle full throttle, and instead it would give me about 1/3rd throttle, and this would last at least all the way through the turn.

I was a little concerned about hitting fuel starvation again, since the last time I was pretty sure I hit it in turn 17 at about half a tank. I wanted to try again, to see when it would happen. This time, I hit it again, just around 1/2 a tank, it didn't stall, but I did completely lose acceleration for a few seconds (felt like an eternity), and it definitely wasn't my VDC or anything, it felt obviously different. Luckily I was able to borrow a extra 5 gallon fuel can from Sick Sideways, so that made the refueling less painful.

My instructor also had me taking a different line for turn 17, which left me hitting less g's while turning, so that also helped with fuel starvation.

Overall things went really well on Saturday. My instructor was very happy with how smooth I was driving, and commented on how I was the fastest one in my group (even including many more powerful cars). It was really annoying though, way too many people out there just cruising around, like they were driving on the interstate or something. There was a couple guys, one in a newer Shelby Mustang, and another in a newer Corvette that were a big pain in the ***, slow as hell, and hesitant to give a point by so I could pass them. I swear in a single 30 minute session I must of passed the Shelby like 4-5 times, each session. :rofl2:

I really, really liked the Star Spec tires, obviously they are a night and day difference compared to the V12's which I used last time, but stiil, their grip was amazing. Temperatures were about 85 with low humidity. I was still able to get my oil temperature to about 260 when shifting close to or at redline, however just a few turns affer shifting 500rpm earlier, the temperatures quickly dropped to 240 and dropping.

Sunday
Sunday wasn't as much of a success, but I still had a great time. I turned off my VDC from the start. I went most of the session and things felt really good, it was great to finally be able to accelerate more quickly out of a turn. However, this did bite me once, where I gave way too much throttle while coming out out turn 16, and I did spin out. Luckily I didn't hit the wall, but I did come about two feet away from it! We talked a lot about what went wrong, and how to correct it, and I felt like I learned a lot from it.

Unfortunately my spin out did unnerve me a bit, which caused me to drive pretty conservatively for the rest of the day, I just couldn't help it. Then, during the third session I started getting a pretty bad vibration in my steering wheel while braking. I decided that since I had a 2 1/2 hour drive back, I didn't want to chance rendering my vehicle inoperable. After talking with some people here though, I wish I continued, since it doesn't seem like it is anything I should of been too concerned about. I think it's likely just deposits on the rotors, since each day that passes the vibration is becoming less and less.

So all in all, I had a great weekend, and felt like I made some good progress. I still have tons of work to do, mainly with consistent threshold braking, and throttle control. From this point on, I'm not going to run with VDC on while tracking, since it just seems like a hindrance in both speed and learning proper car control.

My next event probably won't be until the Fall, it's just too damn hot out. I'm planning on hitting up Sebring again for a 2 day event, and then the new Atlanta Motorsports Park right after that. The only mod I'm planning on doing before then is brake ducting.

I've been putting up videos of each of my sessions on Youtube. I also isolated my spinout:


You can see the rest of my videos here:
YouTube - flashburn2012's Channel

I still haven't finished posting them all though.

Anyway, just thought I'd share my thoughts and experiences with everyone.

Wow, that turned into a wall of text. :rofl2:

Nice writeup. I ran with VDC my first few track days too. I had no idea what it was doing to me until I turned it off. I think things got a lot easier after that.

It is GREAT in the wet though. (Except for that straight line 360 spin in the wet at Grattan) In my wet sessions I feel way faster compared to the rest of my run groups usually.

edit: WOO that spin is way more scary than either of mine. :P

:tup: Good choice. As your experience shows, VDC can make you sloppy with throttle and car control.

Edit: Watched the video. That was close! From what I can see it looks like you got on the gas to hard/early, like you said, and overshot the exit.

Haha, yeah, I was SO close to the wall. My instructor was like "did we hit anything?". If the tire wall extended further, I would of hit that. The impact would of been at a pretty low speed though, it slowed down in the spin really quickly.

Yeah totally. It completely f'ed with my throttle control the first day. I think if I left it on any longer I would just have an even harder time adjusting to proper throttling.

Scary, but a very valuable learning experience!

I really think that in both the 350 and 370, VDC on at the track is a pretty dangerous thing to have. Its way too overprotective. The C6 had a competetive driving mode, that I always ran with on, and it rarely ever intruded, but heck, even on the street vdc can do unpleasant things, like cut engine power when you are trying to cross traffic quickly.

Looks like fun!

From what I see the spin wasnt caused by early apex or too much throttle. You were still turning when you should have straightened the wheel and you lifted. One thing you could have done to avoid the spin was to relax the wheel and steer out of the turn with throttle on. Even if you were to drop a tire off into the dirt you would have gone straight. Dont fight physics you will always lose!

Hmm, I dunno, the early apex screwed me up, so yeah, I could of straightened out earlier than I did. Either less throttle or straightening out earlier would of helped prevent it I think. I really just panicked because I never experienced it before, and completely forgot what I was supposed to do, and before I knew it, it was too late.

:iagree: but I do think he apexed early. It then carried him wide and he kept turning to try to stay on the track. If you watch the lead car in the video, Flash starts turning in a moment after the guy who's 150ft ahead of him. The lead guy late apexed, Flash early apexed, and the ideal was somewhere in between.

There was a nice dirt area next to the track where you could have gone off straight and then recovered back onto the track gradually. It can be hard to fight the innate desire to stay on track at all costs, but sometimes going off in a controlled manner is the ideal solution.

Yeah, one of the master instructors was like "Football field, THAT WAY!" afterwards, lol. Lesson learned.

One thing I like a lot before a track day is to go karting. It gets your hands working quickly and you're just more prepared for reacting to the unexpected. My first few track days, I found that I was expecting the car to do all the work and I had very very slow hands if something started to go wrong.

:iagree:

It was the sudden lift that sent you around. It is a natural reaction at first when you realize you're going too fast for the corner but it is not the correct reaction when you don't have any VDC to bail you out. You can use a small sharp lift to help rotate the car and then get back on the gas to power through, or you could have kept the line you had and done a little off-roading with 2 wheels as there wasn't anything to hit on that side.

Not a bad idea. I heard there is a pretty good kart track in Orlando. Perhaps I'll check it out.

Nice write up! I always learn something and appreciate those who take the time to share the experience. I can only imagine your heart was really racing as you spun out. Thanks for sharing!