I finally made it to a Milwaukee Region event! I was told that this was where the competition was, and it definitely didn’t disappoint! It was a fun battle in STX, which was comprised of 8 vehicles, all of which were BRZs, and most of which were more-or-less fully-prepped for the class. And most of these drivers are much more experienced than myself. I still managed to eek out a 4th place finish, even barely beating the crazy-fully-prepped STX BRZ that whooped my butt at the last Chicago Region event 🙂
Date: Sunday, July 03, 2016
SCCA Chapter: Milwaukee Region (Event #6)
Location: Miller Park, Milwaukee, WI
Weather: Partly Cloudy, Dry, 70-75 degrees F
Car: 2015 Subaru BRZ
Class: 345 STX
Wheels/Tires: 949 Racing 6UL (17×9)/Bridgestone Potenza RE-71R (245/40R17)
Brakes: Hawk 5.0
Suspension: KW V3 coilovers, Raceseng Cas/Cam plates, Velox LCAs
Raw: 60.559 (4th of 8 in Class)
PAX: 50.627 (61st of 187 Overall)
Stiff Competition
I have been told by several people over the past few months that if I really want to see what serious competition is like, that I should attend a Milwaukee Region SCCA event. So I did… and they were right! On Saturday there were 14 competitors in STX. They were mostly BRZs, with a few FR-Ss and a couple Mazdaspeed 3s. I attended Sunday’s event, which only had 8 entrants to STX – all of them BRZs. Some of these BRZs were familiar to me, and some of them were new. In any event, I believe most (if not all) of them, were more-or-less well-prepped STX class vehicles. Some of the drivers were also described to me as “national level competitors.” So yes, the competition would be stiff. A few photos of some of these vehicles can be seen below:
Another Open Course
For the second time in a row, I got to enjoy an open-style course (relative to what I am used to). I love these types of courses very much for many reasons, but I think my favorite part is just how much room you have to choose your own line. Narrower courses restrict your ability to do this, and everyone winds up being more-or-less funneled along the same line from one cone to the next. With wider courses like these, you have to approach the course more like an actual track. “Slow in; fast out” becomes critical because there are lots of long straights – especially in an under-powered car like the BRZ where getting a good run out of a corner makes all the difference. A lot of my focus for this course wasn’t so much on the slalom sections, or other quick transitions, but trying to perfect my line around some of the longer corners. I’ve gotten a lot better over the last few events at reigning myself in on corner entry. As a result, the car doesn’t push wide as often, and I’m missing my apexes less and less often now. That being said, I still miss them way too often (as evidenced by the video below.)
Setup Tweaks
First off, I want to point out that the trimming I did on the rock guards was a success! No scraping occurred at this event, even though I actually had the coilovers set just slightly softer than last time. I’m fairly confident that I won’t have to deal with that issue anymore.
Speaking of softer settings, normally I run with my coilovers’ compression and rebound set to full stiff at the front, and two clicks back from full stiff at the rear. As I’d mentioned in my last autocross post, I was happy with the added roll resistance, but less than enthused with the skittish nature of the car. Even a slightly uneven surface would cause the car to bounce around a bit too much for my liking. So this time around I turned everything down two more clicks; two from full at the front, and four from full at the rear. This was my first time at this venue, so it is difficult to do a proper comparison considering it was an entirely different racing surface, but I do believe this setup works better. It’s close to as stiff as the coilovers will go, but just compliant enough to allow the car to absorb some of the bumps/undulations on the road surface without bouncing all over the place.
I’ve been running with my tire pressures at 31 front / 30 rear, but it seems that everyone runs several PSI lower than that, so I also reduced my pressures to 30/29. I figure that will also help to absorb the bumps as well. I feel as though I’m honing in on the optimal setup for the car now. I’m really pleased with just how neutral the car is. If you push it really hard the rear will step out (which is good), but otherwise it’s quite composed and takes corners without too much drama.
Other Issues
So I’m happy with the current setup, but that doesn’t mean there isn’t room for improvement. There are two issues above all that I really would like to address:
Issue #1: Rev Limiter. I’ve mentioned this before, but today I ran into the limiter on not one, but TWO different sections of the course. The first spot where this occurred wasn’t such a big deal because if I did hit it, it was right as I was about to lay on the brakes anyway. However, there was another spot on course where I was hitting the limiter WAY before my braking zone. In fact, I hit it way before my braking zone on my FIRST (and slowest) run. Staying away from the limiter seemed like a solution that would lose me time considering how far away from the corner it happened, so I decided on a new tactic: upshifting to 3rd. This isn’t really difficult, but downshifting to 2nd is still something I need to work on being able to accomplish smoothly. I can heel-toe on the street, but I’m not adept at it enough to be able to do it while competing. For the time being I simply hit the brakes, and brought it back into second halfway around the next turn. The trouble I had was that I would become very distracted by the shift back to 2nd, and I kept coming out of that turn way slower than I should have, which cost me time. I might need to practice my aggressive 3-2 shifts in my spare time.
Issue #2: Body Roll. Boy is there a lot of it! I knew the car was leaning a decent amount because of the fact that it was scraping the rock guards on the ground, and because I had ridden in another STX BRZ which stayed comparatively flat. However, when I saw the above picture it really drove the point home. Yes the car is on coilovers, but they are KW V3s, which are more street-focused than track-focused. They have relatively low spring rates (about 270 lb-in) compared with other track-oriented coilovers which generally run 400-600 or more. In fact, it almost looks like I’m just about bottoming out the struts in the above picture. This is all a result of what happens when you run crazy-sticky 200 tread-wear tires. More grip = more lateral forces for the suspension to cope with = more body roll.
The ideal solution obviously would be a set of more track-focused coilovers. This isn’t going to happen anytime soon – mostly for financial reasons. Other solutions in the interim could be the use of spring rubbers (rubber blocks that you insert between two coils in the spring to effectively increase the spring rate) or meatier swaybars. Swaybars are a logical solution, but they aren’t the ideal solution because while a beefier swaybar would reduce body roll, it also more greatly couples the motion of both wheels of the axle it’s installed on.
In the meantime, I had a very interesting chat with a certain Moto Miwa, a name some of you might recognize (he was involved in the development of the BRZ) and he suggested raising the car slightly to at least give the V3s a bit more useable stroke to work with. I think I am going to take his advice, and raise the car up 3 collar turns at the front and 4 collar turns at the rear and see where that gets me at the next event. I may also ask an alignment shop to help me mark both -2.5 and -3.5 degrees of camber on my camber plates, so that I can switch back and forth myself. I might try running with -3.5 up front at the next event to see if I feel any improvement.
Unfortunately, the one run I forgot to record at this event was also my fastest, so instead I present you with my second-fastest run. It was only 0.35 seconds slower, but noticeably sloppier in some spots. The three most obvious places with room for improvement in this video are the two wider left-hand turns at 0:25 and especially at 0:49. In both cases I came in a bit too fast, and also turned in a bit too late, completely blowing both apexes. I also fumbled my shift up into 3rd at 0:57, and that distracted me and caused me to screw up that left-hand turn as well. Overall it was a pretty messy run. There is definitely a lot of room for improvement on my part before I can truly say that the lack of modifications to my car are the only things holding me back!
