NASA Oktoberfast at VIR: October 2023
NASA Instructor Clinic Friday + Sat/Sun HPDE
I attended the NASA Mid-Atlantic Oktoberfast event at VIR this past weekend, primarily to go through their Instructor Clinic. I instructed a long time ago (I think 2018 was the last year?), but it was only with the Tidewater Sports Car Club and at NCCAR which is a very “safe” track overall with tons of runoff, zero blind corners, and no real elevation change. It was a relatively low-risk place to go off-track. Places like VIR are considerably higher risk and I spent the last several years going other places and working on my own driving before wanting to sit right seat with a student elsewhere.
With that said, the weekend primary goals were not about my car/driving, but primarily:
Completing the instructor clinic Friday
My student on Saturday+Sunday: getting them aware, smooth, and safe
With the secondary goals being:
Have fun playing around in HPDE4 with all the CamaroStangHellVetteGT3s
Monitor the car for oil-ingestion related knock (running the MK8 “full” retrofit) - I had intentions to swap back to the “basic” retrofit but it was a busy weekend and I just wasn’t feeling like doing that.
Play around with the Brake Prefill ABS adaptation
So how did the weekend actually go?
The entire weekend was BUSY. It was my first NASA event and the paddock was packed. I rolled in on Thursday evening and set up a tent near the lake in North Paddock.
Friday and the first couple sessions on Saturday were 50+ cars on track, one of them being about 70+ cars. Lots of point bys, driving side by side and passing in the climbing esses, and driving off-line more than not. Several sessions were started with double yellows due to track barrier repairs needing done due to the TT or race events right before the HPDE4 sessions.
On Friday night, a very light clunking noise had developed intermittently from the rear suspension. I ended up jacking the car up and found one of the rear sway bar end links had worked loose. The paint markings I put on before every event and/or any time stuff gets torqued helped to quickly identify what had happened.
My buddy Bryan rolled in on Friday night with his MK5 Jetta as he was instructing Saturday-Sunday as well.
My student was driving a gutted Mercedes CL32 AMG - something you don’t typically see at an event. Most of the weekend was spent getting him smoothing out inputs with minor adjustments to his line, and working especially on keeping an eye on the flag stations. He said that turn 3 was his lowest hanging fruit per his last instructor, and by the end of the weekend we were carrying a lot more speed, and way more smoothly through it than how we had started. It was great getting back in the right seat and seeing someone make progress, especially during some of his key “ah ha!” moments.
As for driving in HPDE4, partway through the day Saturday people were leaving or just not going out so the traffic situation improved. I had either a student or a passenger with me in nearly every session, so not fully pushing the car and mustered a 2:20. Nothing near my prior PB of a 2:12.55. The car felt low on grip and I was not looking to feel it out too much with a passenger in the car.
Saturday evening was a lot of fun, there were some other MK7 owners there (howdy Jordan and Lee!) and I ran into a couple other readers of the website as well. It was great chatting with some others who are tracking these cars or dipping their toes into tracking them via a Hyperdrive.
Sunday was even more clear with traffic, and for whatever reason there were about half as many people on track in the first session of the day. I managed a 2:16.84. Still not great, but it is what it is. The tires just didn’t have a ton of grip. People swear up and down the the V730s stay good until the end, but comparing the friction circle graph from May of earlier this year vs this event, it’s pretty clear that they’re falling off in multi-tasking grip (trail braking, mostly) - you can see this by looking at the shape of the outsides of the hits on the graphs below. Pay particular attention in the -0.9/-0.9g area in the lower left.
It IS important to note that this was my first time running the 255/245 reverse stagger setup at VIR… Previously I had the 245s square all around. Comparing tire condition of the 245s in May vs the 255s in October should be relatively comparable (2 track days in Feb + 1 autocross on the 245s originally, and 1 track day + 4 autocrosses on the 255s before the event in October)… So it MIGHT be that they heat cycle out quickly, track conditions while overall similar just weren’t the same, or perhaps the wider tire really isn’t as well supported as the narrower one? I haven’t been particularly happy with the V730s from the beginning so I doubt I’ll be buying them again. Their only saving grace is they’re silly cheap.
As for the rest of the car:
Tune:
One place where the G-forces are improved is in acceleration - about 0.10g average better. The tune has had about 20 revisions since May, and it pulls a lot harder, even on the lower boost map.
Brakes:
I have been playing around with brake adaptations. I’m working on putting together a huge article with details on what I’ve figured out thus far, but to summarize what SEEMS to have made a real difference in my pedal getting extra-sensitive partway through a session:
Overboost in Brake System (11966) - I have some documentation to show this is also known as “fading brake support”. There are modeled brake temperatures (visible in VCDS advanced measure values in address 03)… I suspect that as the brakes get hotter and hotter (based off of a now-incorrect model around STOCK pads) and get grabbier and grabbier. I was experiencing this a bit in May, July, and also once at Fastivus in September.
Brake Prefill (11966) - This is a function that prefills the brakes with a few psi to take up any slack between the pad and rotor based off of how quickly you let off the accelerator pedal. I think my above intermittent problems were a combination of these two things.
As always, MORE TESTING IS NEEDED to confirm it’s fixed for good, BUT considering I didn’t have a single “oh shit” moment all weekend, even in the rain on Friday, I’d say that it seems promising. It wasn’t until Sunday that I was really pushing the brakes a lot harder into the braking zones - interestingly enough it seemed like I could push as hard as I wanted and while ABS would engage, it wasn’t overly reducing pressure and was still slowing the car down at an acceptable rate. ABS stuff is very high-risk to screw with so take the above info with a grain of salt and be careful if you do choose to screw with anything.
Suspension:
I DID remove the 034 lower ball joints before this event. The car just felt way too weird at Fastivus for me to want to keep them on. The car is back to feeling normal, but I do need to figure out a way to add more camber over the winter. I’d like to get to -3.2 to -3.5 deg at least. I reset the Powerflex offset LCA bushings to their max camber setting again, so it was otherwise identical to May of earlier this year.
MK8 PCV:
I ended up running all weekend on the MK8 PCV in the “full” retrofit configuration - utilizing the venturi via a hose from the 034 TMD. Zero problems. The most KR I saw all weekend was -3.0 deg on individual cylinders, or -1.875 deg avg, and it was primarily on my high boost tune which I ran for one session on Saturday. Just to be sure, I looked at the KR a bit closer, below are some snips of the log, left is overall, right is zoomed in one two of the worst parts. You can see all the KR isn’t starting until more than halfway down the back straight. This was purely from running a bit too much timing and/or boost and the ECU is stepping in to tone things down. It was at 22.5psi at 5350 rpm, 4.5 deg of timing, 80F IAT, and 235F oil temp at the point where it started for reference. Not terribly spicy compared to some OTS tunes, but my knock sensors aren’t heavily numbed and I prefer to keep my pistons in one piece.
Hood Vent:
I never went over 250F all weekend. While I wasn’t pushing the car as hard to try for a personal best, comparing an afternoon session back in May to this weekend, there seems to be roughly at least a 10-15F drop in oil and coolant temps overall. Ambient temps were exactly the same at about 70F so this is about as close to an apples to apples comparison as is feasible at this time. Pace in both of these sessions is inconsistent but they’re taken 6 minutes in for reference. Definitely not a substitute for a (properly ducted) oil cooler, but helps nonetheless, and honestly seems to be “enough” to keep an IS20 car happy enough on track.
What’s Next?
So the last event I have scheduled for the year is the Tidewater Sports Car Club December to VIRmember on December 9-10. Come on out and join us, even if you just want to spectate you’re welcome to come for a ride-along and hang out! It appears we have (10) MK7s already signed up, (1) MK8, and a MK5 at this time… so should be a great time!
