It’s been a long hiatus, but things are finally looking like the 2012 season will get under way shortly. Just a refresher on what happened since the last trackday in August 2011 (Mid-Ohio).
I ended take up a temporary position in northern California, hence it didn’t make much sense to send the Miata out west for such a short duration. This ended up becoming more ‘long-term’ than initially anticipated. I have finally decided to have the car shipped out, and it is due to arrive in about one week from now.
There are no immediate plans on the goals for 2012, but since this is a whole new area I will have to learn the tracks all over again.
Once the car arrives I will start to decide on the season goals/budgets.
Now that I have some time I can finally do the trackday writeup for Mid-Ohio with 10/10ths on 8/11/11. Started the day bright and early with the track going hot at 8am (usually tracks don’t allow running until 9am). For the first session I felt completely lost around the track. Having not had too much time to study the course and youtube footage I spent most of the time (with an instructor) trying to find my braking, turn in and track out points. Possibly the worst track session I’ve had since I started. I couldn’t find any sort of rhythm and was starting to wonder why this place was so highly praised…
In the second session I started to find my braking points, which led to better consistency and also allowing for higher corner entry speeds as I could start turning in with the front end loaded under braking load transfer. Things started to click and by the end of the session I was completely in love with the Mid-Ohio Sports Car Course. Best laptime of the session: 2:00.99
During lunch I was able to drive the course at low speed and really pay attention to the different camber and elevation changes of the corners. I got the OK from the instructor to run solo and the previous owner of the ProjectTrackday Miata was able to come by and ride along around the course. With more experience and comfort of knowing the track a bit better the lap times came down, finishing with a 1:56.81 followed by a 1:55.38.
In the fourth session I ran solo and worked on braking consistency and getting the turn in points better. The car felt great and getting the right braking points to allow for better turn-in, coupled with the lack of a passenger brought the best lap time down to a 1:53.87 followed by a 1:54.00 for Session 4.
After the fourth session I rode with a Spec Miata racer who showed me a slightly different line, especially on entry into ‘Madness’ (Turn 4) and ‘The Carousel’ (Turn 12). Watch the video posted last week (the one with no passenger) and you’ll see the difference of the suggested line. When I went back out for Session 5 (2:30 of track time in 1 day!) I tried out this line and found that I was easily matching the best times from the previous session, finishing off with a string of fairly good laps. I would say these adjustments to the line were worth about 1s per lap:
Lap times from the final session of the day
The points/marks I was using for the track were as follows:
Turn 1: slight touch of the brakes at 100(ft? I assume the markers are in ft), 3rd gear, turn in. Avoid rumble strips on track out
Turn 2: Up to 4th gear on the straight, brake at 200ft, car pointed between the ‘L’ and ‘M’ on the walmart billboard, stay near the inside of the corner. Full throttle and aim for the apex when the car is lined up with the jegs billboard
The Kink: Flat, minimize steering as much as possible
Turn 4: Brake @ 425 from redline in 4th gear, downshift to 3rd, go deep into the corner and set up on the inside of turn 5
Turn 5: Brake to set the car up for the corner, stay on the inside, power out after the car crests to avoid rear wheelspin going over
Turn 6: Brake before the new surface patch and turn in when the front tires go on the new surface, power out
Turns 7-8: Flat, set up for straight line braking for 9 as much as possible
Turn 9: Brake, turn in carrying as much speed as possible for the run up the hill
Turn 10-11: Shoot for “Ohio” on the bridge, upshift to 4th, turn in @ 300, get as close to the right guardrail as possible. Slight brakes, turn in for 11, leading edge of the rumble strip is the apex
Turn 12-Finish: Aim for the middle yellow ‘box’ on the opposing fence, enter the corner on the inside, brake and downshift to 3rd in a straight line to set up for the rest of the corner. Minimal steering to make turn 13, track out and avoid rumble strip on exit, start another lap… This was the line I used in the Session 5 video, shown again below:
The data shows that I could have made up another 0.5 seconds on the final sector (thunder valley through the carousel to the start/finish line), with the optimal time on RaceChrono reading 1:52.23. All in all a very fun and productive day, quite a good outing for my first time at this track. Hope I get to go back sometime and give it another shot…
On the subject of tire wear and the new alignment, I checked the tires throughout the day and found that the wear was much more even than previous trackdays. The car handled beautifully all day long and aside from getting more negative camber in the front I am very happy with the numbers. I ran cold tire pressures of 30psi all around to start, then took out 1psi in each corner after the first session.
As I mentioned earlier, due to personal commitments I am having to call a close to the season early. This is the final event I will be running in 2011 (unless I can get a ride at a trackday somewhere in CA).
I’ll post a more comprehensive writeup about the trackday once I get settled down out west. For now I’ll just leave you guys with the video from the final session of the day around the Pro course:
The first few laps are a bit quiet as there isn’t much traffic around, then I catch up to a train of cars and reel in an orange Spec Miata as we go at it for a lap or two at 5:50 into the video. A F430 Challenge blows by at high speed at 19:26, the sound alone is enough to make you drool…
As I mentioned earlier, I have to end this season of trackdays early due to personal commitments. The checklist of items to do kept me busy for the last few days:
Change motor oil + filter (M1 5W-30, M1-110 Filter), $30
Change differential oil (M1 75W90 GL5), $10
Brake bleed + top off (ATE Super Blue DOT4), already had the fluid
Alignment, $75
Rotate tires
Adjust ride height (12.5″ F, 13.0″ R)
I couldn’t get exactly the amount of camber I wanted in the front (-2.3deg) but it was pretty close. For the rear I got exactly the numbers I was looking for:
Front: -2.1deg camber, 4deg caster, 0 toe
Rear: -2.0deg camber, 1/16″ toe in
Final season maintenance budget is at: $1,060 + $115 = $1,175
Three days until Mid-Ohio with 10/10ths Motorsports. We will be running the Pro Course. Track goes hot at 8am on 8/11/11.
With the summer in full swing I finally get my second track day this season, a two-day event at Putnam Park with 10/10ths Motorsports. I let my girlfriend drive the car on Saturday, followed by me on Sunday. Ambient temps were in the 9oF+ range most of the weekend and the car handled perfectly all weekend with 31psi tire pressures all around (front shock 100%, rear shock 50%). Hot pressures were somewhere in the 36psi range.
Pre-trackday maintenance involved the usual brake bleed, lubing the caliper slide pins and also changing out the thermostat on the car ($20). In order to offset some of the costs for the season I had also managed to sell off the OEM rear springs ($25) and stock seats ($125), bringing season costs to a total of: $1,190 + $20 – $25 – $125 = $1,060. I will need to change the engine and diff oils before the next event, but without any unforeseen problems should be able to close out this season under budget.
With my instructor I kept on experimenting with different lines in turn 8, finally coming to the conclusion that a tighter line coupled with trail braking on entry was the fastest way around. The laps felt quick, but never matched the 1:26s I got at the last outing, possibly due to trying too hard and overdriving the car. I will have to dial it back on entry to get on the power sooner and see if that yields the results next time at Putnam.
Miatas out to play!
For the last session of the weekend we got together the remaining Miatas and went out together. Leading the pack was Aaron in the white NA, followed by Bryce in the red Spec Miata, with me and Bruce (Blue 10AE) closing out the 4-car train. The starter got on the radio and said “this can’t be good…three miatas going out together” right before the out lap. The rest of the story can be seen in the following video:
As Aaron lost the rear exiting turn 1, he spun and exited the track to the left. Bryce was on his tail going into 1 and spun towards the right. At that point I made a decision that trying to make the corner was probably risky, then promptly took the option to go between both spinning cars. No harm, no foul… Nobody was hurt or resulted in any damaged vehicles, and a good laugh was had once we all got back to paddock after the session. Getting to drive alongside a good group of drivers with similar machinery makes trackdays so much more enjoyable!
Also encountered my first red-flag drill during session 3. I actually missed the flag at corner 5 and saw the red flag at corner 7 as I exited 5. Good reason why we practice these sort of drills, just shows that I need to pay more attention to the flag station at 5..
On the subject of entry fees for 2011, the most recent trackday brought the total to $330 + $205 = $535
Now for the sad news… I will have to end the third season of Project Trackday early this season as I will be temporarily relocating to California in the fall. If all works out I may look into renting one of 949 Racing’s Miatas to run at Laguna Seca, however that will be seen. Between now and then I plan on one more test’n'tune at Gingerman on July 19th or 20th, followed by the season closer at Mid-Ohio on August 11th.
Another weekend of autocross with IndySCCA, this time around the Carbon Motors plant in Connersville, IN. After finding out that the rear springs were binding on the car Tom spent all Saturday with a group of Indy mod-car drivers sorting out the problems on the rear end. The result is that the car is now planted in the rear, maybe a bit too much because we were suffering with a lot of understeer all Sunday. I will need to measure the motion ratios and then we will be changing the spring rates out to hopefully resolve this handling issue.
Once again, I finished in 5th in class (out of 6), though this time it was mostly my fault as I overdrove the car in my final two runs (of 4), causing DNFs as I ran wide on a turn that had a tightening radius. Tom did well and finished 3rd in class, 0.067s behind second place. We have started to run two runs before driver changes to alleviate driver switch problems. Due to our differences in physical size it takes a while to do driver changes, and we were being fairly rushed several times doing driver changes after each run in previous events. I tried to get camera footage of the runs but unfortunately the tiny bumper camera did not have enough of a wide angle lens and also ran into some vibration issues. Regardless, here is the video footage from one of my runs, though you have been forewarned!
This event brings the season entry fees up to $305 + $25 = $330.
Just also want to post a status update on the scheduled test’n'tune at Gingerman tonight. Weather forecast is not looking good (50+% chance of t-storms after 6pm) so I am going to skip it this time around. Will hopefully try to get out there sometime mid-July, keep posted on planning on the miata.net forums.
I’ve been getting a lot of messages regarding people interested in making a set of seat mounts as I showed on the blog and I had already posted the PDF part drawing. So what is it going to take to make a set of these on your own?
You will need to source your own machine shop to cut the plate metal (3mm for steel or 5mm for aluminum). In order to water jet the part or run it on a CNC mill you probably need the IGES format CAD file. Here [download v.2] is the file I sent to the water jetters to be cut, you will need to bend the brackets at 90deg for the side mount section, and 15deg down for the mount bolt tabs once the plate steel (or aluminum should you choose to go that route) is cut.
Seat mount v.2
This version [download v.3] should mount the seat as low as possible to the car without removing the seat mount humps in the car, and is 1/2in lower than the brackets I had made. You will probably not be able to increase the layback on the seat beyond the stock sidemount layback as the rear of the seat will be very close to touching the mount bracket at this position. Note that the ‘stock’ position is already approximately 3-4deg layback due to the difference in height of the mounting humps in the car, and the FX1 Pro side mount points result in more layback than the bottom mount on the seat.
Preparation for install will require mount holes drilled on the mounting tabs, I recommend test fitting the seat in the car on the brackets, using some sort of device (e.g. laser pointer) to locate the hole positions and then marking those spots on the brackets before drilling to ensure accuracy.
The use of the part design is completely free. If you would like to donate to Project Trackday, feel free to click the ‘Donate’ link on the right side of the page. This is not required, but every bit is definitely appreciated regardless of amount. All donors will be mentioned by name (or alias if you prefer) on the Thank You! page. If you need help customizing the IGES file for better fitment, feel free to leave a message in the comments (include your email address in the appropriate box so I can contact you directly regarding customization).
Warning: These CAD files are offered purely for educational/entertainment purposes and Project Trackday offers no guarantees, nor is it liable for any damages, losses, injuries or expenses either consequential or incidental from the use of these drawings. By downloading these files you agree to this disclaimer. Use of the CAD files for profit is strictly prohibited. Remember that motorsports are dangerous, so you should always install safety gear properly.
Got around to washing and cleaning the car finally. The wheels themselves probably took as long to clean as the rest of the car. See the pictures here.
As for an update on the season and upcoming events, IndySCCA points event 2 and 3 have been completed. I am still co-driving Tom’s Reynard RF-85 in C-mod, now having finished 5th in class three times in a row The previous outing was not representative of what the car was capable of due to rain washing out the event after 3 runs, we should be closing in on some trophies in the coming weeks. Add another $25 to the season entry fees for the autocross and we’re up to $305 for 2011 so far.
Upcoming events include a test’n'tune at Gingerman Raceway on either the 15th or 22nd of June, followed by another run with 10/10ths at Putnam Park on July 3rd. If you are in the area and want to meet up for the test’n'tune at Gingerman for either the 14th or 21st, feel free to leave a message
I will be at Gingerman for the Test’n'tune on Tuesday 21st, and then back at Putnam Park with 10/10ths for July 4th weekend. Come by and say hi if you can, always glad to meet readers of the blog!
In order to get a true 10Hz refresh rate in RaceChrono with the Qstarz 818XT on WinMo 6.1 I have run it with reduced NMEA sentences (lines of GPS data), running with only the RMC (Recommended Mimimum Data for GPS). I have finally found a workaround to get it to hold steady at 10Hz with all of the default NMEA sentences (GGA, GSA, RSV and RMC). For those that are interested in finding out what each of these sentences are, here is a useful page of information on GPS NMEA data.
