We had enough testing on different surfaces that it was time to go back to home turf to go up against more regular competition to see how she would stack up. I wanted to continue dialing out the slow speed push coming out of turnarounds so we dialed the front bar down from 6/6 to 5/6 (rear bar at 5/7). I also raised front rebound up a click to keep the weight on the front tires after hard braking coming into a sweeper. We ended settling on 29/27psi tire pressures and this greatly helped with transition stability.
NNJR SCCA - 10/10/2015
Hez and I codrove as usual and Jon came up from PA as a third driver to give her a test run since he would be running Lupa the next day with the Philly SCCA. After some tweaks to tire pressures, we were getting happy with the handling. Jon was able to get Lupa to 3rd fastest STR time, only 0.3 seconds off the top STR time.
NNJR SCCA - Meadowlands, NJ - 10/10/2015
I wasn't going to be able to make the Sunday event at Warminster so Hez and I swapped cars and he drove Lupa down for the race with the Philly SCCA. This time Hez, Rad and Jon would be codriving.
Jon driving Lupa
Philly SCCA - Warminster, PA - 10/11/2015
Warminster is known for being very transition heavy so they opted to run a 1psi pressure differential front to rear (29/28psi) to get the rear to swing around faster. Jon ended up taking the win in STR and ended up 5th in PAX overall out of 140 drivers, collecting enough points to secure the Philly SCCA 2015 Driver of the Year award (congrats Jon).
Philly SCCA - Warminster, PA - 10/11/2015
I do have to double check the rev limiter settings. She's hitting redline like a stock S2000 which isn't right since the redline should be set to 8500. That makes it even more fascinating that she's doing so well since we're leaving plenty of speed on the table if we're not able to rev her up all the way.
This past week we were threatened to get hit dead on by hurricane Joaquin but somehow the storm system moved far off shore and so I seized upon the opportunity to take Lupa out to the Meadowlands to do more testing instead of just sitting home to watch Netflix and chill.
MotorsportsNE Autocross - 10-4-2015
The major problem we had today was the cold. Temperatures in the morning hovered in the 50s and the strong winds at the Meadowlands coupled with overcast would make it difficult to keep heat in the tires. Luckily, there was very low turnout today and with Hez and I codriving, we were able to get almost back to back runs, keeping the temps right in the sweet spot. The course was nice and long and had both fast and tight elements. It lacked a bit of flow in the 2nd half of the course making it not the best course possible but it was good practice and more importantly ideal conditions for testing car setup.
The first thing I noticed on my initial baseline runs was that transition speed had improved a lot with the increased bar settings front and rear but she was still a bit too stable and on the pushy side. I reverted the rebound changes I made to the front shocks at Nassau Coliseum and put them up 2 clicks again. This helped keep the weight up front after braking to get better turn in. We then fiddled with the tire pressures, running a bit higher pressures in the rear. Our times kept improving and Hez laid down a nice class-winning run on this setup (Go Bumble Jockey!).
Although Lupa was working, I didn't like the higher rear pressure setup since I prefer equal or lower pressures in the rear so I wanted to do a bar change but the quick driver changeovers made this very difficult. I also felt that a bar change was warranted as she was still not rotating in the tight corners under power the way I wanted. We got a short break in the action due to a minor incident and we were able to quickly adjust the rear bar up to 4/7 and then brought the tire pressures equal all around. Unfortunately, the downtime had cooled the tires and the pressures had dropped to 28psi in the front. We didn't have time to add more air so we set the pressures to 28psi all around. This new setup worked great, she was rotating better around the tight stuff but introduced a bit of instability in the high speed transitions. To get the rear to settle, I lowered the rear pressures to have a 1psi split front to rear and achieved what I felt was a good balance. Personally I feel a good test for car balance is when even small pressure changes in the tire pressures can change the balance of the car very easily.
It's hard to gauge Lupa's true pace when we're not at an SCCA event with other fully prepped STR car so it's very easy to dismiss a win as an artifact of just having low turnout but thankfully Evan was there in his BS National event winning Corvette to use a reference point and Hez was only off by 0.2 in PAX against his fast time which isn't bad at all considering we actually ran in the earlier heat when the course was still not very clean and the sun hadn't come out yet so that's very encouraging.
Lupa taking her first win
MSNE Autocross - 10/4/2015
In short, she's feeling pretty awesome. She transitions really well and does so in a very stable, confidence inspiring way. You can get very aggressive with the the throttle early, and power out of sweepers. In the tight stuff, she can tuck in nicely with just enough rotation to let you dance around under power. The direction so far is great and I'm very pleased that we're slowly approaching the similar balance characteristics to Bumblestook (minus the added power and insane grip of Hoosiers). For the next event, we'll be running higher pressures but with the same 1psi different front to rear since both Hez and I felt a bit less responsiveness in the tire at these lower pressures.
On a personal driver note, I pretty much hit a cone every run. This is oddly very encouraging as over the years I've found myself driving less and less and as a result I've been getting further from the cones. Hitting cones means I'm actually trying hard enough to get close and I can go faster. I'll have to clean up my driving though if I want to actually do well in real competition. Right now I'm just too focused making sure the car feels and behaves exactly the way I want.
Some things to think about over the winter:
My front shocks are already at full soft compression. Even though they're working well with this setting, maybe I should revalve them and remove some of the gas pressure so the dial is more in the middle
I need to raise the car about 0.25". The springs have settled to a very low ride height that I don't like. She needs more height to let the suspension work.
We need to shift the front subframe so we can get a proper alignment and squeeze out another 0.1-0.2 degrees of front camber.
Ugh, I wish we had the faster AP1 steering rack (can't do anything about this)
After checking out Skaria's 18" Advans at the last event at Nassau Coliseum, I think I may go with an 18x9 and run a 255/35/18 to get an even more crisp steering repsonse.
The season's almost over but I'm glad I was able to get even this limited amount of testing done to Lupa before the winter. She's very close to what I envisioned in my head and she'll only get faster from here.
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
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.
After months of installing parts and getting her ready, it was time for Lupa's first autocross in full STR trim. Although I had adapted a lot of Bumblestook's settings over to Lupa to try and mimic her balance, I knew it would take time to get her the way we wanted since we had no actual starting point to compare against. We were also on fresh RE71s that hadn't been fully scuffed in so their performance was going to be reduced. Still, it was time to focus on the important thing at hand which was to try and get the balance to a good starting point.
Lupa ready to run - NNJR SCCA - 8-30-2015
I took the first run as a general systems check to make sure there were no issues with the car. There was no rubbing and we were going over the undulations with ease. We were good to push hard now to find the limits. I immediately noticed a very large amount of understeer that needed to get dialed out ASAP. We softened the front shocks and Hez took it out for a run and it was a bit better but still pushy. We also started off running 33/29psi but started to decrease this delta to find the balance and gain traction. I brought my pyrometer but the battery ran out so we were adjusting pressures blindly here unfortunately.
We increased rear compression and added more rebound all around to try and find that perfect balance between being critically damped and keeping the weight where we needed it to be in the transitions and powering out of sweepers. The goal wasn't necessarily to get the fastest time as it was to push the car to explore the limits and make all the necessary adjustments to dial out any observed weaknesses. Every run Lupa was feeling more and more balanced and the setup was moving in the direction we wanted. On the final run, which Hez took, it was important to drive for time rather than for tuning so he drove it normally and set our baseline. We were only a few tenths off the fast STR cars at the end the the day. This is very promising. You can see the difference in how the car behaves in the video of our fastest runs. My time was set on my third run and Hez was on his last run. You can see how much less effort it takes to drive her fast in that last run. He looks like he's on an early morning Tofu delivery run despite clocking in a respectable time.
I'm highly encouraged by Lupa's performance. She unfortunately still exhibits push under power coming out of the tighter turn arounds and could be faster in the transitions with quicker weight transfer. We also ended the event running as low as 27psi all around. That was just a bandaid to try and balance her out but I don't think this is ideal as I'm sacrificing some of that sharpness in steering. There's also too much rear toe preventing her from rotating under power the way I want. The RE71s also seems to not roll much under load so I think we can afford to reduce some of the rear camber and salvage some straight line speed.
Below are the changes I plan on making before her next event. I think she's going to be up there competing for the top spot very soon.
Alignment:
Front: -3.1, a hair of toe out (current -3.1, 0 toe ....well actually unknown since it shifted due to tranny installation)
Rear: -2.2, 1/16" (0.06) total toe in (current -2.4, 0.18 toe in)
Pressures:
Probably try 29/27 but bringing a pyrometer to make proper adjustments.
Also, big thanks to Kamil at Clean Cut Vinyls for making my awesome car/class magnetic numbers and other decals.
One of the major mechanical issues with Lupa is 2nd gear popout under deceleration. This is due to a known defect that affected a small range of S2000s between late 2004 and early 2005 and is covered by TSB 05-009. Unfortunately Lupa's VIN falls into this affected range of cars but I didn't trust taking my car to any dealer even for warranty service so I had originally planned to just have the transmission rebuilt professionally by Billman. However, after we swapped in an AP1 tranny in Bumblestook, I already had a perfectly known working low mileage AP2 tranny just sitting around so I decided to just swap it in instead.
Transmission swap - 8/15/2015
This time I employed the help of Jonathan (Soul Coughing on S2ki Metro) to do the swap for me. Jonathan had already done several clutch, transmission and diff jobs before and as a fellow dual S2000 owner, I felt confident he could do the job right. While we were going to swap the transmission anyway, I decided that even though I only had 55K miles on her, it would make good sense to replace the clutch as well. We put in a brand new OEM AP2 cluch, flywheel, pressure plate and bolts.
Old clutch and flywheel out, still in great condition - 8/15/2015
New clutch and flywheel in - 8/15/2015
Lastly we also swapped in Bumblestook's spare diff pumpkin which has a new ATS Spec III clutch type diff put together by Brian at Karcepts. The OEM torsen is more than capable but I prefer the feel of a clutch type diff and by keeping Bumblestook and Lupa on the same setup, it would be easier for me to continue a similar tuning philosophy and have matching spare parts.
ATS Spec III diff ready to go in - 8/15/2015
When Rad found his diff mounts were torn during the NJ ProSolo earlier this year, he found a method to just fill the OEM mounts with polyurethane for a cheap DIY poly mount alternative. I had him make a set for me too and we installed those along with the diff to minimize any play as we try to get power down to the ground.
DIY Poly filled OEM Diff mounts - 8/15/2015
Although we ran into a few annoying issues (mostly because of my swaybars, stiff mounts and dual exhuast was in the way), everything went in smoothly and she's now driving perfectly. I'll have to get another alignment since you have to lower the front subframe to swap transmissions on the S2000 but I probably won't do that until after I come back from Nationals. The good news though is that she's ready for her first event which should happen in 2 weeks barring any further issues. I'll have to make time to drive her quite a bit until then to break in the clutch and diff but that's something that I can at least enjoy. It's been almost 3 months since I ordered the very first part for this STR build and I can finally say all the major mechanical work is done and it's onto having fun and seeing how she stacks up against the other STR cars that have had several years to be developed already.
Huge thanks to Jonathan for doing a great job with this part of the project, taking his time to do it right. It's good to see fellow S2K owners who appreciate the need to do things right and not take shortcuts.
After test fitting the STR spec wheels and tires, it was clear that I'd need an alignment ASAP if I wanted to have Lupa drivable and not ruin my tires or fenders. With SJF Performance unavailable, I was lucky to get squeezed in for an appointment at Camber Toe Performance in Lynbrook this past Saturday.
First alignment - Camber Toe - 8/8/2015
Photo by: Joe Miranda / Camber Toe
Since I haven't autocross Lupa yet, I wanted to just set an initial baseline alignment based on some numbers I had been toying around with on paper. I'm almost certain I'll be re-aligning again before this season was over so a good ballpark would be all that was needed. I ended up with the following alignment specs:
Front:
-3.1 Camber
0 Total Toe
Rear:
-2.5 Camber
0.18 Total Toe In
I'm glad we did the alignment since I was running almost a full inch of toe in at the rear and definitely wasn't running enough camber up front so my fenders were in danger of some carnage if I got full compression load due to a bump or something. I also asked them to bend the fender tab in the front for a little bit more tire clearance. There's no need to do a full roll on +63 offset wheels with 255 sized tires.
We're almost there. I'm shooting to take her out to her first event later this month.
