[Autocross] NCCAR Autocross Non-Points Event w/ THSCC+TSCC
Making a pig dance around a Miata course
What changed since last time?
Items changed since last autocross are bolded.
The biggest change I’ve probably made to the car yet is the IS38 turbo + my own DSG tune. I was actually at NCCAR 2 weeks prior for a private test day which I basically just used for getting the ECU and DSG tunes sorted (well, mostly sorted). The car definitely has more top end, along with less transient response which will take a bit of getting used to. I could have gotten on the throttle a tiny bit sooner. The biggest game-changer in doing my own DSG tune was being able to set the shift points. I essentially programmed Sport mode to keep the lowest gear possible (with a bit of overlap to avoid hunting up and down) which worked out great. The one downside was I hadn’t found the correct tables yet to shorten the Sport mode shifts (but Manual mode worked just fine w/ 0.100-0.150 sec shifts)… so most are in the 0.400-0.500 sec range. I do believe I have figured it out since this event though.
The other change was the front LCA bushings which were replaced with JXB sphericals. Now that I was able to drive the car in anger on 200TW tires to better assess the front end grip… they definitely help tighten up the front considerably. Having the added caster back was nice as well - it certainly helps with the front end bite and getting the car rotated earlier w/ larger steering inputs.
And if you’ve seen the latest video about the MK8 Retrofit, you know about the modified MK8 PCV valve which was mentioned. I was doing initial testing on my own car this weekend, to ensure nothing unexpected happens and verify crankcase pressure (vacuum) levels prior to putting it on a friend’s car. More on that below.
Making the best of a very tight course
While NCCAR autocrosses are a lot more limited in what you can do on the course, there were many pinch points and (IMO) overly tight elements that generally favored much narrower cars.
The weather was great, if a bit hot. The car had really good grip immediately from the get-go, and the course was LONG just because it was at NCCAR. The plus side was that there was half of the road course to drive back to paddock and get things cooled down. I ended up not having to spray the tires at all. I had no codriver for this event again (non-points, he wanted to drive his C5 Corvette… I can’t blame him).
The course was TIGHT and I was not expecting to do as well as I did. Somehow I managed to hustle the GTI through it all well enough to place pretty decently + win XA. This was a different club (Tarheel Sports Car Club) so there wasn’t a “bump class” for all the Provisional Classes like Tidewater Sports Car Club usually does.
Run 1 - 68.292 +2
I set the tire pressures at 33psi front and back to start, not exactly sure how high they would get front vs rear because of the length of the course and surface I haven’t autocrossed on (with this car/these tires). I initially ran run #1 in Manual mode.
My first run out of the gate the car felt REALLY good. One issue was I kept finding myself either short-shifting (because the IS20 liked to be shifted around 5500-5600 rpm). I hit a few cones but based off of seeing some of the other times from the first 3 heats, I knew that there was actually a decent chance at placing pretty well.
I found the tires had grown to about 36psi up front and 35 psi out back by the time I returned to grid.
Run 2 - 68.150
Run two I set tire pressures back to 33 hot up front and 33 hot out back. This seems to be about where I like the balance of the car overall with the idea being that the fronts would continue increasing in pressure - probably right back to about 35 psi. I also ran this time in Sport mode and was able to just focus on car placement. I cleaned it up and took a few sections more conservatively - this would ultimately end up being my fastest run overall.
Run 3 - 72.068 +DNF
My third run I screwed up immediately after the start where I revved the car too high in 1st gear and it delayed the shift because I was trying to run it in Manual mode again. The run was complete thrown away by the time I reached the 180 turnaround. I overdrove the car a bit in the slaloms/offsets leading up to that and pushed way out past the gate. I took the remainder of the course a bit slower pace to not add any more heat to the tires and get back to grid where I’d reset the tire pressures to 34/33psi while hot.
Run 4 - 66.896 +2
This last run I was pretty happy still with my 68.150 so figured I had nothing to really lose. I went back to Sport mode on the trans. I drove with a bit less aggression than Run #3 but coned it away just trying to take one of the slaloms a bit too tightly with my inside rear tire (one early on, one a bit later in the course). I kept driving like normal just to see out of morbid curiosity what kind of time I could have run… and basically was exactly what I thought: I was probably leaving roughly a second on the table. The car has really good potential overall.
Car/Driver Summary:
I was real happy with my driving at this event. There’s always a bit of room for improvement there, and I think I’ll get a bit more comfortable as I train my right foot to anticipate the IS38 lag. I may also experiment with some ECU related stuff to help transient response.
Since most of the events this year have been at VMP (Virginia Motorsports Park), I’d really like to see how the car feels back there at the August 3rd event coming up for a real idea of how the changes have affected it. Based strictly off this event, the suspension feels great. It’s certainly not “the best” or anything (the Koni Special Actives are not ideal for lowering), but it’s good enough and has a fair amount of mechanical grip. I think I’m done chasing time/setup in that aspect for this year. I DO wish the 034 springs sat just a tiny bit higher, but moreso for daily reasons (pulling in and out of my driveway mostly). That’s something that will not be addressed until next year (if at all).
This was a Saturday event that did not count for Tidewater Sports Car Club season points unfortunately, with Sunday being Points Event #5. I had originally planned on attending that as well, but some personal stuff came up and had to bail on that event.
Event Results Summary
1st (of 5) in XA
3rd (of 135) in Raw time
8th (of 135) in Pax time
Continued research on the 15-16 GTI PCV problems:
Pictured above is the ventilated MK8 PCV valve I ran on my car for this event. My car has not exhibited any smoking problems on track since the full retrofit (or even basic retrofit)… but as I’ve been getting feedback/experiences from others also doing it, it seems that 2015 and 2016 GTIs (and likely 1.8L) cars still have issues. I’ve found a few 2015-16 MY owners who’ve had luck with the AP PCV valve, while also having problems with the BL or MK8 PCV valves. I believe the 2015-16 CXCA and CXCB engines were built differently than the 2017-18 were, and I covered some of the possibilities here:
Why install the vented valve on a car that doesn’t have problems?
Well, simply put: I want to make sure it doesn’t introduce any NEW problems on a known good car.
In a nut shell, the amount of oil accumulated in my catch can was minimal (a few drops, maybe a couple more than typical?). This was also the first time autocrossing on the IS38… so that could have had some kind of effect as well. I was expecting there to be either no real big change… or completely fill the thing up. Fortunately it was the former so now it is time for the next phase of testing.
We have another autocross event next weekend back at VMP. The plan is to take this valve and put it on Jacob’s 2015 GTI that we previously discussed last month. We shall see what happens soon enough!
Photos from the event:
Once again, thanks to Josh with @SixthMediaGroup for the shots!
