[Autocross] Points Event #6 with TSCC: August 2024
Terrible driving, but major win for the MQB community
Start of the Day: Wrenching in the Name of Science
Ventilated MK8 PCV valve allows vacuum to be pulled on the cam cover to not create a pressure differential when oil covers the engine block blow-by passage under hard braking + RH turns.
If you saw the Trip Report from Points Event #4, then you know about the Jacob’s GTI smoking even with the MK8 Full Retrofit. Some further research was done after that event which led to this PCV update video. I modified a MK8 PCV valve to allow it to pull vacuum on the cam cover as well as the engine block blow-by passage, with the theory/thought process covered in that video.
This valve was first run on my own car at the July NCCAR Exhibition Autocross, where it was used with no issues introduced and crankcase pressures kept in check.
We both arrived on site early to swap the PCV valve out. I’ve had these PCV valves installed/removed so many times that I think we were done in under 15 min start to finish.
More on this experiment below!
OCD Side Quest: Organization in Packing for Events
One of the things I’ve been wanting to do for a while is stream-line the process of packing all my stuff for an autocross or track event. I’ve been unpacking and packing tons of things in and out of my toolbox for years. All the time spent getting it together (and not forgetting anything) has really made me feel overwhelmed when trying to balance home/work/hobby balance. There are enough other prep things to do between events, and spending a solid hour trying to pack everything each time gets really old.
I opted for some Dewalt ToughSystem 2.0 boxes to start building up a track/autocross tool/supplies set that can just be dropped into the hatch and be ready to go. I went with these because the drawers are waterproof (IP54), notably less expensive than the Milwaukee Packout system, and it helped that Home Depot had a big sale going on currently, so I picked up the following for $320 or so out the door with taxes due to the $100 discount:
DWST08450 (1) Rolling modular toolbox base
DWST08330 (1) Three-drawer toolbox
DWST08165 (2) Small modular boxes
I played around with a few different packing methods and was pleased to find out that set up the right way, you can keep the back seats up. I’m still figuring out exactly what it will be filled with, but expect a future article and/or video in the future. In the meantime I just tossed all the tools I’d expect to need this weekend, mostly for the PCV swap and normal wheel torqueing/etc.
Even though everything isn’t completely how I envision yet.. it was really nice just grabbing a few large boxes and dropping it in the car. Bonus is that I could take the entire setup to grid to hold tire gauges, set helmet on top, etc.
Super Close Battle in XA
Thanks to Josh with @SixthMediaGroup for the photos!
The weather leading up to this event was calling for rain initially. Lo and behold, it was actually pretty darn hot out at 80F ambient and sunny. So naturally I did not bring my sprayer, and I had my codriver again (after a couple events without one). While the tires didn’t really fall off a cliff grip-wise… I suspect that spraying them may have helped to some extent.
There were no setup changes to the GTI for this event vs last time.
Run 1
Tire pressures were started off at 33/33psi, and I took my first run which I felt was pretty conservative and pulled off a 39.904, while everyone else was in the 40s-42s, including my codriver Logan - who ran a 40.600 +2. I was feeling pretty good about the car overall at this point.
Runs 2 and 3
I blew runs 2 and 3 - the car was a pushing mess and I was just driving sloppy and having a hard time truly looking ahead. The course we were running had a lot of elements spaced pretty far apart and while I feel like I usually do pretty well, I just could not get things together. We were playing with tire pressures a bit, trying higher pressures overall per some input from national level STH autocrossers online. I believe 36/36 was the highest and it just was not getting any better. I ran a 40.528 +1 and a 40.439, while my codriver ran a 40.246 and a 40.107 +1.
Rick in his 2017 Alltrack (featured here) was hot on the heels of my first run with a 39.940 (less than 0.030 off).
Run 4
We returned the tire pressures back to the tried-and-true 35/33psi hot and the feel of the front end started to come back, but in my opinion wasn’t where I needed it. I was definitely feeling the pressure to do well and messed up my line and ended up with a 40.586. My codriver did a 40.102 +DNF, and Rick did a 39.796 +DNF.
Run 5
With tire pressures again reset to 35/33, I was absolutely feeling the pressure. I KNOW there was at least an attainable half-second left in the car, but I just wasn’t driving very well. At this point I figured that driving aggressively was not working for me and tried to tone it back a bit to at least do a little better than my first run. I managed to go a tiny bit faster with a 39.864.
And then my codriver managed to come out of nowhere and put down a clean 39.703.
And then Rick was able to put it all together to put down a 39.783.
While it was a really good battle between the three of us - It was pretty frustrating knowing that I was in 3rd place with only 0.161 sec keeping me out of 1st.
I REALLY wish I had video of our runs to compare - but it appears the SD card I used in my GoPro got corrupted. In the meantime, here is a video from the 2nd place XA Alltrack:
I was recording data via Simos Tools which can be helpful, but with no video AND no GPS, it’s hard to discern driver differences. One interesting find is that my codriver is overdriving the HELL out of the car… 25psi, 180 deg steering wheel angle, and 100% pedal position…
So this might explain why the front end lacks grip any time he’s codriving…
Results Summary
3rd (of 5) in XA
6th (of 10) in the Provisional Class (PAX based vs all CAM classes and XB as well) - look again at just how ridiculously fast that Tesla in EVX is!
11th (of 53) in overall PAX
8th (of 53) in raw time
Definitely not my best driving and it really showed.
Experimental PCV Valve Results
So how about Jacob’s 2015 GTI running the modified PCV valve?
He got through all (5) runs with zero smoking problems. This was huge because he has blown huge plumes of smoke at the other two TSCC autocross events he’s run this year. In fact he has never been able to complete all of his runs without smoking. The first time was with his OEM PCV valve, and the second time was on the MK8 Full Retrofit.
He’s running the MK8 PCV (ventilated to the cam cover) w/ Full Retrofit using the 034 TMD, and has the Jack Spania Racing catch can kit inline between the Venturi and the TIP just like my car. We wiped out the catch can in the morning prior to his runs (at the same time as when I swapped the modified valve in), and checked again after all of his runs.
The catch can had basically nothing in it - just a light film at the bottom, same as what mine gets after a few autocross runs or hundreds of miles on track.
Once again, if you want to get the background as to why this modification was done/necessary, check out this video.
There are a few other people who I’m keeping tabs on with these modified valves, and will be putting more info together very soon.
The next autocross event is not until October, so hopefully that’ll allow me to catch up on some of the other stuff I’d like to publish.
