Project Trackday

Another fun test’n'tune event at Gingerman Raceway yesterday.  I got the opportunity to try out the new front brake pads and also experiment a bit with my line at the 2.21mi 2010 layout course.  Firstly I have to say that I am very happy with the performance of the Carbotech XP10.  With the Yellowstuffs I was finding that I had to press harder on the brake pedal as the pads got up to temperature, but on the Carbotechs the bite feels a lot more consistent between cold and hot.  Overall the braking power between both compounds is hard to judge because it feels like there is now too much front bias as the XP10s have more bite than the EBCs.  That’s not to say they have more stopping power, but just that the brake balance is a bit off.  I will either need to change the rear pads/rotors to Carbotech XP8/XP10 or consider getting a brake proportioning valve installed.

No open-wheel cars showed up, therefore the 3hr test’n'tune was split amongst two run groups, with 1.5hrs of track time per group.  As for the event, there were a few drivers in the novice group that had never been to Gingerman before so the first session was run under full-course yellow (no passing).  I went out on track first but by lap 3-4 was catching up to the back of the group so I decided to pull in and request some open track space.  Back out again and a further 2-3 laps into the session I’m back stuck behind again.  With no point-bys and basically getting 1 lap of running between warm-up and cool-down laps I decided to scrap the session.

After the run the course director suggested that I try running with the intermediate group to see if that would get me some more open track.  Obviously I was slower but at least I could point-by the faster guys and focus on my own driving.  I tried different lines and shifting during the session, setting several 2:04.7s laps (about 4 laps timed at 2:04.7 during the session).  That’s a slight bit slower than the times I estimated from reviewing video footage from the last time at Gingerman (2:02 +/- 1s) but the track and ambient temperature was also about 15F cooler, and the Azenis are probably closing in on the end of their usefulness.  All in all I feel like I was driving pretty hard on the tires so I’m not sure where the discrepancy is in the timing, though I will review the on-board footage in more detail later.

(note:  after reviewing the previous footage it looks like I was running a low 2:07 last time around, so a 3 second lap improvement this time around is a pretty productive day!)

At least I wasn't being easy on the tires...

On-board footage from session 2 of 3 with the intermediate group:

$60 entry fee for the test’n'tune (not bad for 1.5hrs of track time!) puts the season entry fee total to $815.

A few minor things going on the last week.  I decided to lower the car a little bit to reduce the amount of wheel gap and lower the ride height by switching the perch settings on the koni sports.  Both front and rear shocks were set on the middle perches, resulting in a ride height of 13.5″ front, 14.0″ rear.

Top: Middle perch setting, Bottom: Lower perch setting

For the front I was able to get the spring compressor on without removing the shock from the car, however due to space constraints in the rear (namely the upper A-arm and drive axle) I had to remove the rear shocks to get the rear adjusted.  Current ride height is 12.875″ front, 13.75″ rear, though I do expect the rear height to still settle a bit more.  I’d like for the rears to sit at about 13.5″ but I’m not confident it will get there..

Also took the opportunity to change out the front brakes as they were just about at the end of their usefulness.

One shot front pad...

Going with vented blank rotors from a national chain auto parts store ($40 for two) and replaced the front pads with a set of new Carbotech XP10 pads I purchased from NASAforums ($75).  The A/C parts were also sold off (-$50) so the running total for the season is now at $750.

Was a little concerned initially about the brake bias difference between running the Carbotech XP10 in the front and keeping the EBC Yellowstuffs in the rear, but after doing some brake testing it seems to be very well balanced under braking.  Will get a better idea of how good these Carbotechs stand up when I head back to Gingerman next week.

The brake pedal was feeling slightly mushy after the trackday so I finally got around to bleeding the brakes and checking the pad wear today.

Rear rotors and pads still in great condition

There is some minor scoring on the front rotors, but no cause for concern.  Originally thought I was running low on pad material in the front but after removing the caliper it looks like there is still a good amount of front pad too.  I need to lube up the upper and lower caliper slider pins as the pad wear is uneven.

Outside had is wearing a bit more than the inside pad

Bled all four corners and the brake feel is back to normal again.  While I was at it I also checked on the spark plugs to see how they were holding up.  They all look to be in pretty good condition.  I still need to do a writeup of the last trackday, so I’ll get to it later this week.

Spark plugs still looking good.

A few more items off the checklist and a first chance to test out the new shocks this weekend.  Changed the diff oil with some Mobil1 75W90 GL5 diff fluid ($7) and flushed the brake system.  Fresh ATE Super Blue (extra inventory from 2009) in to get ready for the trackday in less than 1 month.

Sunday was IndySCCA’s first solo event of the year, starting out with a ‘fun event’ (i.e. no points awarded) at 16th Street/Bush Stadium in Indianapolis.  Was extra cautious in the first run because I did not know what to expect, but the car felt quite well balanced right off the bat (35psi front, 36psi rear with all shocks set to full stiff), just some minor oversteer.  Turned the rear shocks back a half turn and the car settled to be very nice to drive.  For the first time today I also ran in the STS class although the car still needs a lot of work in order to be competitive in the class.  Beats not having anyone to run against at least.

…and of course, here’s the video of the final run (now available in 720p HD!).  Clocked in at 0:40.505, which put me in 2nd place for STS:

As I am keeping track of event entry costs, this one is the first of the season and costs $20.

The weather is finally starting to improve here and the car was pulled out of storage on 3/17/10 (special thanks to Tom W. for letting me keep the car in his garage over the winter!).  A fresh oil change (Mobil1 5W-30 Full Synthetic, M1-110 oil filter) today is the first step in preparations for the 2010 season.  I will flush the brake fluid next week (weather permitting) and check the brake pads/rotors for wear.

Koni Sport (Single adjustable) shocks to replace OEM shocks

The plan is to also get the newly acquired Koni Sport shocks on the car and a new alignment before the auto-x season opener on 4/11/10.  Currently it looks like I will be sticking with the stock springs for at least the first half of the season, though upgrades to the sway bars may be in order.

Note: I don't have any pictures from Sunday on track so all the pictures in the post are ones that were taken Saturday...

Back early on day 2 to prepare for another day I arrived around 7:20am just as the sun was coming up.  It was still pretty cold but the forecast was a dry and sunny day for the entire day.  First thing I did was to check the brake pad wear, especially in the fronts.  Being this was the first time I had asked so much of them I wanted to make sure that there was still plenty of pad material on there because I knew I was going to ask more of them on the second day.  Surprisingly there wasn’t much brake wear at all, so all I can say is that I am extremely pleased with the performance and durability of the Yellowstuff pads.  (This was again verified at the end of Sunday, and I’m confident these pads have plenty more track time left in them)

The morning started as usual with a class session, and then back on track where for the first time we tried yet less braking between turns 3-4 and holding 4th gear all the way through from the exit of 2 through hard braking for turn 7.  This was a vast improvement from staying in 3rd all the way through 4, upshifting on the exit and then back down to 3rd on the entry to turn 5 as I was forced to keep the momentum in the car to prevent it falling out of the power band.

Something clicked in this first session early on going into turn 7 and it made a world of difference.  I experimented with braking late and turning in just the same time I was starting to release the brake (before the front could decompress) and the turn in was so sharp that I had to turn the wheel back a bit.  The following lap Mike told me  to treat turn 1 like “an autocross sweeper” and I did the same late brake and turn in before the front decompressed, and ended up coming in to turn 2 so fast that I had to really adjust my braking into the corner.  Finally I was starting to use the load transfer characteristics of the car instead of trying to fight it…  The remainder of the lap I focused on hitting the points at the higher speeds I was now achieving and using the load transfer to my advantage.  Mike was very happy with the progress and mentioned that I had now “opened a whole other door” and was “on another level now”.  He mentioned that he had wanted me to get to that point at the end of day 2, and was happy that I was already there so we could keep on moving the yardstick further.

We discussed staying in 4th gear all the way from midway down the main straight until turn 7 and then I took a ride with him to see how it was done.  The goal was ‘Momentum Driving’, and it was extremely important since the Miata was so down on power compared to the rest of the field.  I noticed that exiting turn 2 Mike was able to keep his car at 4300+rpm and therefore had good power out of the corner.  My goal was to exit the same corner at enough speed not to get bogged down in 4th coming out of the corner.

Session 2 we worked on momentum driving and I focused on looking for a visual cue for turn 8 (which had been the corner I was still early apexing a bit because I couldn’t see the apex or exit until 3/4 ways through the turn due to the rise.  Finally I found a good reference point and was able to start consistently hitting the apex.

Coming into turn 1 I was braking late, using the load transfer to turn in and then just a light push on the brake to get more front bite into turn 2.  Going through 3 I lined up for 4 and then braked not to slow down but to settle the front end before turning into 4.  Braking into 5 to get front turn in and then flooring it to hard braking for turn 7, turning in early to clip the apex and flooring it to the entry of 8, taken in the outside middle of the seam on the track, turning in and waiting for my visual cue before getting on the gas.  On the brakes into 9 towards the outside middle of the seam, crossing over to the inside of the seam through 9 (not using the inside curbing) to look for the curb to the right of the pit entry, getting my rear left on that and then the front right over the apex of 10 to do it all over again.

In session 3 I was held up late in the session in the turns for a few laps by a 996 Turbo and Mike told me to stay behind it, testing my ability to follow and on my lines (not watching the car in front’s lines).  I had hit all of the cues and was not letting another car in front get me distracted or off my line even though I was having to brake 150ft earlier into 1 due to the car ahead.  Once we ended the session we stopped in the pit to discuss the session and Mike gave me the go-ahead to do the final session solo.

Cleared for solo in session 4

The final session of the weekend was a combined session with both Green and Yellow groups running together, and was 35 minutes instead of the usual 25 minutes.  Having watched a Yellow only session I was a bit concerned about the number of cars on track synchronously (28 cars on track for the yellow group alone), but as they pulled into the paddock several cars packed it in and called it a day.  Start of the 4th session I was just going to go out and do my own pace but making sure I kept an eye on faster cars coming up, and I felt once I got into a rhythm it really wasn’t a problem at all.

Mike suggested I get a feel for how the car feels different through the turns without the extra weight of an instructor in the car, especially on the left handed turns where there was no long that extra mass on the inside of the corner.  It was definitely different not having the extra weight, the car was accelerating faster (no surprise), and was quicker through the left turns (4 and 8 ) but it felt more on edge on the right turns (as I was going quicker and also because the CG of the car had been shifted).  At one point I peeked down and saw I was hitting 100mph into braking for turn 1…

Late into session 4 (maybe 5-10 minutes until the end) my fuel gauge was starting to creep towards empty and I was following a 944 around the track.  I wasn’t much slower or faster, and over an entire lap I felt I was maybe about on parity with it even though it had the go in the straights to pull away.  I contemplated on pulling into the pits and calling it a day but I was confident that there was enough gas to run out the session.  A lap or two later as I was exiting 10 the 944 spun in front of me, and in hesitation I lifted off the throttle too quickly, inducing a big oversteer moment.  In my lack of experience I instinctively tried to countersteer to catch the slide and got into a huge tankslapper.  Once that happened I knew I was in for the ride, put both feet in (brake + clutch) and hoped for the best…

I hit the exit hay bails on 10 hard going backwards, but I already knew what I had done wrong..  Getting off the gas in panic was the first mistake, but secondly I should have been more conscious of the track layout and known that 10 was the only corner with a guardrail to hit, so I shouldn’t have even tried to save the slide.  Shortly after the track crew, ambulance and Mike were alongside, and I was asked if I was hurt in any way (no.).  Mike mentioned the damage was minimal but I really didn’t want to see what damage I had done..  I drove the car back to the pitlane, sat for a minute and then came out to see the damage.  The rear finish panel and the passenger tail light was cracked, but other than that no other parts would need replacing.  Mike mentioned that if that damage had happened early on Saturday we would have just duct taped the broken plastic parts and kept on going all weekend.  No mechanical damage whatsoever.  How lucky was that!?

Assessing the damage once I got home...

Headed up to the tower for a debrief/report of the accident and then I headed back down to pack my things for the long trip home.  Plenty of time to think over what had happened.  I came to the conclusion that it was a rookie mistake to get spooked at an incident happening right in front of me, but other than that I had made huge strides over the weekend.  I can’t wait until summer ’10 rolls around so I can do it all over again!  This will be the last event for the 2009 season for Project Trackday and all I can say is this has been such a blast so I would highly recommend to anyone who has the interest and means to get into this sport to not be scared away by how much it can cost.  I pulled it off for under $4000 even though at times it seemed like it was improbable, and I had the best summer/autumn ever getting to drive this car around.  I competed in 5 autocrosses and completed 1 weekend trackday (with over 200 minutes of track time).

During the offseason I will be doing some repairs to the car, and depending on the budget I may be upgrading the suspension (shocks and springs) or wheels/tires (going to a 15″ rim to open up my tire compound options).  As for Project Trackday 1.0, I completed my goal so this portion of the project is complete.  Next season I will be keeping track of how much running a season (entry fees, repairs, etc) costs to give people an idea of how much it costs to run a car through these events…

’09 has been a blast, see you in ’10…

As expected, the EBC Yellowstuffs pads are quite a bit more agressive than your run-of-the-mill brake pads.  As a consequence they tend to dust up quite a bit more as well.  After 350mi (most of which was highway driving) you can see that there is quite a bit of brake dust on the rims already.  It’ll be interesting to see how much brake dust buildup I get after a trackday…

Lots of brake dust already...

On an unrelated note, I decided to remove the factory strap down “baby teeth” hooks over the weekend.  Doesn’t seem like much, but the mass of the 6 bolts and the 2 hooks alone are probably around 1.5kg (won’t really know exactly how much until I put them on a scale).  They are all 14mm bolts, and can be removed without too much fuss with a wrench (not socket wrench, it won’t fit up in there!), though if you have one of those ratcheting wrenches that would be a big plus!

Small pieces, but they add unnecessary mass

Not only is this for weight savings, but also opens up the front air dam for if I decide to install a mesh grille at some point in the future.  Hard to tell from the picture, but the radiator has had some minor damage from rocks in the past, so it may be a worthwhile investment.

Open mouth, no teeth

Another break from the rain today allowed me to finish off preparations on the brake system for trackday/auto-x.  I went with new rotors and pads all around because the old rear rotors were shot, and the fronts weren’t worth resurfacing (only $10 more per rotor to get brand new ones!)

First I started off with the rear rotors.  See below on the condition of the old rear left rotor, not looking too great.

Rear left rotor is not in the best condition...

First thing to do is to retract the caliper piston by turning the manual adjustment screw.  Find the 14mm bolt below the brake hose and remove the bolt completely as it is just a cover for the 4mm hex manual adjustment screw inside.  Turn the hex screw counterclockwise to retract the caliper piston.  I removed the master brake cylinder reservoir cap just in case, and kept going back and forth to make sure the brake fluid did not overflow (note:  not even close…)

The 14mm bolt below the brake line is a cover for a 4mm hex nut that retracts the rear caliper piston

Brake Master Cylinder reservoir cap off just in case...

Once the caliper piston has been retracted the caliper can be removed by unscrewing the bottom caliper pin bolt.  It is covered by a plastic cap in the picture below.  Remove the cap and then use a 14mm socket to remove the caliper pin bolt.  Now the entire caliper should swing up, giving you access to the pads and rotor.

Cap for the caliper pin bolt needs to be removed to access the 14mm bolt

I tied the caliper up and out of the way so I could take pictures of the process, however this is not necessary.  The old pads come off pretty easily here, however the old rusty rotor had rusted on and seized to the backing plate.  Couldn’t get the damn thing off with several whacks of the rubber mallet.  Instead I put a bolt into the screw thread hole on the rotor and turned it until the bolt pushed the rotor off the backing plate.  Worked like a charm!

Caliper retracted and tied to suspension with some twine

Finally the rotor comes off!

Be careful when removing the old pads, making sure to make note of how the various springs are placed on the pads.  I cleaned up everything with a bit of brake cleaner and then proceed to install the new rotor on there, temporarily holding on the rotor in place with 2 wheel lugnuts.

Shiny new rotor...

Then the new pads with the guides go on the caliper frame.  I went with EBC Yellowstuffs as per tefnut’s recommendation as he has tracked his Miata before and says lots of nice things about them.  Unfortunately here I forgot to take a picture of it all assembled back together.  A dab of anti-squeal on both surfaces that will touch the caliper, and then I removed the string and lowered the caliper back in place.  Putting the caliper pin bolt back in I applied a generous amount of high temp brake caliper grease on the bolt first:

Green stuff is high temperature brake caliper grease.

Now everything reassembles back together.  Remember to replace the plastic cap over this 14mm bolt.  Now we need to adjust the brake caliper back with that 4mm hex screw again.  Turn the hex screw until the pads are in contact with the rotor, and then back off by about 1/3 of a turn.  Replace the 14mm cover bolt on over the hex screw, replace the wheel and then the first corner is done!  Repeat the same procedure for the rear right.

One brake rotor/pad done!

Rear right, before the change

Rear right, after the change...

Now for a cold beverage break and a back stretch!

Onwards with the front brakes!  First the front right.  I removed the wheel, and then removed the lower caliper pin bolt (14mm) first thinking I could pretty much folow a similar process to the rears.  Wrong!  I had to remove the entire caliper frame in order to remove the old rotor

Couldn't find a way to remove the old rotor without removing the caliper frame first

There are two 14mm bolts holding the caliper frame to the suspension.  Remove these and the entire caliper frame (with caliper attached) will come off, along with the rotor.

Removing the caliper frame bolts...

With the caliper+frame out of the way a new front vented rotor finds its home, temporarily held in by two lugnuts.  You can see the caliper + frame sitting on top of the old rotor to the left.

Shiny new vented front rotor

Once again, out with the old pads, keeping all of the springs and the other metal clip.  In with the new EBC Yellowstuffs front brake pads.  I reassembled the caliper frame to the car, using some loctite blue on the caliper frame bolts.  The only thing holding your brake caliper to the car is these two bolts, so better make damn good sure that they aren’t coming out!

Loctite blue theadlocker on the caliper frame bolts

With the caliper frame + caliper that can rotate (remember the 14mm bottom caliper pin bolt is already removed!) back on, compressed the caliper piston with one of the old brake pads + a clamp to get it to fit around the new pads.  Once again, keep an eye on that master cylinder reservoir to make sure nothing is about to overflow, brake fluid will eat right through the paint in the engine bay!

Clamp pushes the caliper piston back

With the piston depressed the caliper can rotate back into place over the new pads, and the caliper pin bolt can be replaced (after getting a nice dose of high temp brake caliper grease of course!).

Three down, one to go!

Three down, one to go.  Now repeat the procedure for the last corner and you’re all done!

Front left rotor is probably the only one not in terrible shape. Doesn't matter, it's still getting the same treatment as all the other corners

All done!

Now make sure to bed in your pads as per the specifications stated in the instructions.  I drove out of town to some open roads to conduct the bed-in procedure.  The brakes definitely feel much better than before and it seems like I don’t need to step so hard on the brake pedal to get the same braking input now.  The car is much more poised and confident under hard braking, though we’ll see how it performs at the track…

The first batch of ordered parts arrived today, and since the weather was nice out, that alone was reason enough to work on the car…

UPS dropped off the following items:

• Motive Products Power Bleeder
• ATE Super Blue Racing DOT4 Brake Fluid
• Brake cleaner

First things first… Gotta check that the power bleeder is getting a good seal with the master brake cylinder.  Hook it up without any brake fluid in it first…

Power bleeder hooked up to the MBC. The Motive Products #0111 has the aluminum adapter specifically for the Miata

Pump until 10-15psi and check pressure gauge to make sure that it is maintaining that pressure (no leaks!)

Pressure holds steady...

Now release the pressure and add in some brake fluid

ATE Super Blue Racing DOT4

… And then pump until 10-15psi (I went with 12.5psi here, just down the middle of the recommended from Motive Products)…

ATE Super Blue gets pumped into the MBC.

Now the bleed order is as follows (according to the good folks at miata.net forums):  RL, RR, FR, FL.  Easy way to remember is counterclockwise starting at the rear wheels…  I jacked up and removed the wheel on the first one (RL) to show the bleed valve in pictures, but there is enough space to do the brake flush on the rears easily without having to remove the wheel.  For the remaining corners I didn’t remove the wheel…  My bleed valves had little rubber plugs covering them, and a gentle pull removes them easily.  Just remember to put them back on once you’re done!

Wrench on bleed valve with homemade catch bottle

You can purchase some catch bottles at your favorite auto store, but I had an old bottle that I never use sitting around, and the extra plastic hose was provided with the power bleeder kit, so I just made my own.  Since the old fluid was amber, I just let it bleed until the fluid had completely changed to the color of the ATE Super Blue.  Turning the bleed valve with a wrench starts the bleeding process.  Make sure the catch bottle is above the bleed valve so you can see any air bubbles that come out during bleeding.

As for the fronts I needed to jack it up a bit to have more space to fit my arm behind the wheel.  No need to remove the wheel, but I found the clearance on top of the wheel to be a bit too tight to fit an arm behind the wheel without jacking it up.  As always, safety first, and make sure you either have blocks or the e-brake on before attempting this!

For the future I will be alternating between the ATE Super Blue and the ATE TYP 200, both are exactly the same specification brake fluids, but having different color brake fluids between flushes makes it easy to see when to close that bleed valve.

For those of you that are keeping track of the expenses on this project, the power bleeder isn’t exactly cheap at $68, but it’s a one-time cost and the car will need at the very least a brake flush every summer.  As for the amount of brake fluid you need to do the flush, I bought 2L just to be 100% sure I had enough to do the job (I’d be pissed if I started and found out half way that 1L wasn’t enough), but it took less than 1L to do the brake flush, so I have an extra 1L of unopened ATE SBR for some other time…

First impressions:  Maybe its the placebo effect, or maybe the old fluid sucked, but I’m liking the new brake fluid.  There seems to be more feel to the brake pedal now (I don’t feel like I’m stomping on the brakes before I get any deceleration), though I haven’t gotten the brake system hot enough to evaluate improved brake fade characteristics yet.

Still more work to do on the brakes, but I’ll get to those when the parts arrive…

Edit:  Just an addendum to this post.  If there is still brake fluid in the power bleeder when you finish flushing the system, turn the bleeder on its side so it doesn’t pick up any more brake fluid.  Continue bleeding the brakes a bit more from the brake closest to the brake master cylinder as the level in the reservoir drops down to between the MIN and MAX lines.