Testing at NYR SCCA Autocross

After yesterday's alignment it was time to get some testing done. With no other events within a reasonable distance, I decided to make the NYR SCCA event at Nassau Coliseum. While I don't have anything against the NYR courses, the Coliseum doesn't provide a good surface to actually do any kind of tuning that would work anywhere else except maybe FedEx field in DC but if anything I'd get some data points running on a low grip bumpy surface.

NYR SCCA Autocross - 9-20-2015

Right out of the bat, the bumpiness of the lot was giving me problems with Lupa skipping all over the place making it hard to time the turn in and brake points. I remembered that I had done some funky shock settings last event to compensate for the weird alignment so I dialed the front compression down 1 and front rebound down 3. This greatly improved the front end response but she was still neutral with a slight leaning towards being pushy at the limit.

NYR SCCA Autox - 9-20-2015
Photo by: Rev Match Racing

For the afternoon runs, I opted to raise the rear bar up another notch to 4/7 and this worked magic. Finally she was giving me that telltale jiggly butt behavior you expect from a S2000. It was a bit too much though since it was a tiny bit too loose under power. To fix this I dropped the rear pressures down a 1psi and finally we hit the perfect balance of twitchiness and stability. With the times fairly stable, I started dropping pressures equally on all corners and dropped a good 0.8 seconds simply by dropping the pressures around 1psi. I ran out of runs to do more pressure testing but I'll be doing that in NJ instead where I can keep more variables constant. For my own notes, I ended up running at 30/29psi. I don't think I had a single clean run but it's all good. The important thing is that Lupa is feeling better and better to drive. The transitions, especially slaloms, are much better than last event and I can actually use the power to get that rear rotated now. Looking forward to the next NNJR event to give her a go on some higher speed, higher grip corners.

Not sure if autocross or rallycross lol
NNJR SCCA Autocross - 9/20/2015

Go Fast Alignment

We're fresh back from Nationals and with the lull of general frantic scheduling of work on cars, I wanted to take advantage and have Steve at SJF Performance implement the changes I jotted down after the first event with Lupa. (As a side note, HUUUUUUGE congratulations to SJF for the awesome 1-2 victory in the new CAM-C class in that beastly F-body)

Lupa's 2nd alignment for 2015 - 9/19/2015 - SJF Performance

I could already tell that my alignment had shifted after the first alignment after we did the transmission swap but the question would be by how much? Unfortunately it didn't look good. We could only get -2.8 max camber from the front driver side but could get a whopping -4.2 camber from the passenger side. Clearly the front subframe needed to be shifted in order to get the specs I wanted. This proved to be a bit tricky but with some help from Pete and a crowbar, we were able to get -3.0 camber on the left side which Steve then matched on the right. We probably really need to actually do this correctly one day so it's even left and right but it'll do for now since we hit the target settings. Caster was set to 5.5 degrees.

Trying to get frame alignment holes lined up - 9/19/2015

Crowbar + wood + BFH - Working that front subframe - 9/19/2015

I had initially wanted to reduce my rear camber down to -2.2 but it seems that with the current ride height, the minimum rear camber was -2.4 if we wanted to get the rear toe the way I want. This was an ok compromise since the rear toe is super important on the S2000. Get this wrong and you might as well pack your bag. Too little and you got yourself a jigglybutt monster, too much and you're basically driving a FWD car with massive push. I was thinking of doing 1/8" (0.12) total toe in but with the slight increase in rear camber from what I actually wanted, I opted to dial this down to 1/16" (0.06) total toe in. I definitely would not recommend going down this much without the correct spring and sway bar combination or things might get a little too exciting on the street. The final alignment specs and other fancy tidbits are shown below.

2nd Alignment Specs - SJF Performance

Wheelbase 0.1" off due to front subframe alignment

SJF Performance

While the car was on the lift anyway, I figured I'd take the opportunity to adjust the sway bar settings and endlink lengths since it's much easier than doing it on site (even though it's still relatively easy to do with the Karcepts bars). The front bar has now been cranked up to full stiff (6/6) up from 5/6. The rear bar I dialed up to 3/7 from 1/7.

Adjusting rear sway bar to 3/7

Adjusting front sway bar to full stiff

Lastly, I have enough miles on the diff now that it's finally broken in so it's important to get a fresh fluid flush to make sure she's in tip top shape.

Fluid flush on the ATS Spec III diff

So there we have it. All the changes from last event put into place I'm going to try and run higher pressures again with the reduced camber. It should make her faster in the transitions and be closer to the optimal pressures for this tire. It should make her easier to use power and the diff to get the rear rotated around tighter spots too. Luckily, tomorrow there's a NYR SCCA event at Nassau Coliseum so I can give her a quick spin to see how I like the new settings. Nassau Coliseum is definitely not a lot you want to be tuning your suspension on so I probably won't be making massive changes but I do expect tighter corners than NJ events so that will help me pinpoint any slow speed corner weaknesses.

Some good news though is that I ended up not needing any of the new aligment bolts, washers and nuts I ordered for her so now I have a spare set (to my other spare lol). No seized nuts! We can all celebrate that.