NASA's 25 hours of Thunderhill.
Shed Racing joins Miller Motorsports
For the world's longest endurance race
By: Tom Aiken

Marcus Miller and Scott Lipton were the designated Sooners for the event, leaving for Thunderhill early on Thursday, and were the 5th team in line when the gates opened.  They were able to secure an excellent area in the paddock, with electrical power, only a couple hundred feet from our space in the hot pits, and relatively close to a semi-improved bathroom.  They got approval from NASA for the spot, then unloaded the ITA car (AKA the 25 hour car), and relaxed for the rest of the morning.  Around lunch time, they decided the weather was nice, so they should start to get set up, so they left the warm dry administration building for the 2 minute drive down to the paddock area, and by the time they got there, the wind had picked up and the rain started.  They managed to set up one canopy and huddled under it for shelter from the storm.  I arrived at the track an hour later, followed by Tim Gray with his RV, and John and Sean Neilson with their enclosed trailer.  The trailer and RV were set up in an "L" shape to block as much wind as possible, and canopies were set up to make a 20' X 20' garage and kitchen area. 

Setting up in the rain.

Finished Paddock area

Morning broke with good weather for the Friday test day, clear and chilly.  The rain had ended late Thursday afternoon, and although we did have a bit of a swamp in the back of their assigned pit box to deal with, in general things were starting to dry out.  Scott Miller showed up around 9 AM, towing the spare Pro-7 car behind his Lincoln.   The extra car was there to rob parts off if we needed to, and to get Sean and Tim more time on track, as neither of them had driven Thunderhill before.  Crew members Grant Conley,  Bryan Crall and Angie Balcomb showed up after breakfast, as did Robert and Mary Miller.  Robert Wils showed up later with another RV, for crew quarters.

The team pit box

Things got off to a rough start, when Marcus went to start the race car and discovered a dead battery.  Once the car was started, a new rear tire rub was discovered on the driver’s rear, as well as some intermittent electrical problems.  While John and Marcus were sorting these problems out, Tim and I took my truck and headed to town to get fuel for the test day, and went by the lumber yard for some plywood and 4x4s to bridge the pit-box marsh.  We got back and built the pit bridge, while Marcus and Sean took turns bedding brake pads and scrubbing tires for the race, and getting Sean some time to learn the track. 

During the morning testing, we also discovered the rear camber settings are radically different from side to side (zero v. -2º ), and the ride heights were off.   After the morning testing, the crew swapped the front corners to bed in the second set of brake pads, and we mounted up the rain tires on the Pro-7, which I took out to turn a few laps and scrub in the rain tires.

The radios were barely adequate, and we never got a really accurate assessment of our fuel consumption, although we did manage to have a nice fuel fire, which was successfully extinguished by driver Sean Neilson on the back straight. It seems the fuel cell vent wasn’t in a really good place, and some overflow was ignited by one of those pretty Mazda RX-7 backfires. The errant vent has been relocated, and a check valve added.   

Fire Marshal Sean (thanks to Doug Macmillan for the photo)

The car was slower than it should have been.  Marcus's best time in the Pro-7 car is a 2:13.xx, and normally is in the 2:15 range.  The ITA car by class rules is allowed wider tires and better suspension prep, but the best time we were able to get all day was a 2:18.xx.  The car has the engine from the Pro-7, but with a better exhaust setup which should give a nice horsepower improvement, but even though it had better suspension, more power and more rubber, the times were slower.  For a grand finale, the transponder quit working, so we were not able to post a qualifying time.

Even though we weren't all that fast, we did keep the car pretty much in one piece, something that can’t be said for all of our competitors.  A 944 driven by the "Seattle Endro" team rolled in practice.  Nobody was hurt, and the crew hammered the roof  back into place, and installed new windshield.  They had it ready to race with time to spare. 

This car rolled in practice.  This is after the repairs.

Friday evening was spent doing last minute items, like installing the video camera, and applying a couple dozen new stickers.  We also needed to remove the transponder from the Pro-7, and install it in the ITA car.  Everyone knows, the more stickers you have on your car, the faster it goes.  We also applied tape strips to the rear window, to reduce the brutal headlight glare from other cars.

Stickered up and ready to race

Ron Swett arrived Saturday morning, with his driver's gear, ready to be the gas-man for the whole race, and he and I made a last minute change to the location of the pit marker light, moving it from the roll cage inside the passenger door to the roof just in from the rain gutter.  We also added a yellow stripe to the roof above the passenger side door, to make the car easier to identify in the dark.  Sean took the car down to verify the spare transponder was working properly, which it was.   

At about 10AM cars started to line up on the grid.  Because of the lack of a qualifying time due to the transponder failure, we were gridded near the back of the pack.

On the Grid  (L-R) Ron Swett, Tom Aiken, Scott Lipton, Grant Conley, Scott Miller, Angie Balcomb, Bryan Crall, Mary Miller, Marcus Miller, Bob Wils, Robert Miller

The Drivers: Sean Neilson , Scott Miller, Tom Aiken, Tim Gray, Marcus Miller

After the National Anthem, the PA system announced the words we had been waiting for:  "Drivers, Start your engines"  It was show time.  Unfortunately the F-15 flyby by the Air Force was delayed due to weather in Oregon, but they did come by about an hour into the race.

Air Force F-15 Eagle flyover

Sean Neilson drove the first stint, and he strapped in, and set out with the rest of the field for the pace laps.  The first lap, the pace car brought the entire field down pit road, to demonstrate the pit road speed limit.  For us this turned out to be 4000RPM in Second gear.  The next time around the pace car came into Pit road, and the green flag flew.  The race was on.

Because we didn't get a good fuel consumption test, the plan was to do this during Sean's stint. The car has a 15 gallon fuel cell, but are only allowed by the rules to put in 10 gallons of fuel per stop.  The idea is to make sure there is less than 5 gallons in the tank for all pit stops, to preclude any chance of overfilling the tank and causing a fuel spill.  Any significant fuel spill brings a five minute penalty, which we wanted to avoid.   The only active pickup in the fuel cell is on the right side, and Thunderhill is mostly left turns, so the theory was that we would have plenty of warning before the cell ran dry, when it started to sputter on one of the few right turns, we would come in for fuel and a driver change. It seems our theory sucked, as the car sputtered one time before the engine died from lack of fuel.   Sean rolled the car on the escape road before turn 6 and waited for a tow back to the pits.  The car was in a safe spot, and race control didn't want to bring out a full course yellow, with pace car to retrieve our car, so we had to wait until there was a gap in the race traffic to tow the car across the front straight.  Unfortunately this took about 10 minutes.

Ron Swett, ready to fuel the car

Once the crash crew delivered the car to the pits, Ron dumped in 2 jugs of gas, and I got behind the wheel and went out for 5 or 6 laps, to burn off a little fuel, then I came back in for a quick gas and go stop to top off the tank and get us back on our planned fuel schedule. I went back out for a little over an hour, when I came in and Scott Miller got in the car. Scott's session was uneventful.  Bryan's friend Charles L. showed up to offer help Saturday afternoon.

Tim Gray took over from Scott, and after about 20 minutes went off in the turn 5 bypass. When he came back on, the low hanging panhard bar (The panhard bar keeps the rear axle in the proper position) caught on something, and broke. Sean, Scott and I were all experiencing a bit of wheel hop under hard braking, which certainly didn't help things, we think the bar was probably weakened a bit, and his off was just the last straw.

Robert Miller and Grant Conley work on the rear suspension, while Bryan Crall inspects the shock towers

John Neilson, (Sean's dad) whipped out the welder and some scrap steel and repaired the panhard bar, which was reinstalled, and Tim went back out to finish his stint. I think we only lost 30 or 40 minutes.

Tim completed his first stint into the darkness without incident. Marcus took over the car, and immediately had an electrical problem that left 2 of the 4 headlights dark. The car is set up with two Dick Cepek 130W off-road spotlights pointing forward, and two 100W PIAA lights angled to the sides to light the apexes. A flaky switch left the two spots dark, leaving the apex lights the only illumination. A fuel pickup problem also surfaced with the cell, causing the car to sputter after burning only ~6 gallons of fuel, but the cause would be a mystery for a few more hours. Marcus hit pit road complaining of missing, and gas man Ron Swett threw in a can of fuel, after which Scott Miller fixed the electrical problem bringing the primary lights back online. Marcus went back out, and with the ability to see where he was going, he was able to pick up the pace, setting the fastest lap so far, a 2:17.xx

Twenty minutes after returning to the track, one of the brand new Mazda Factory Miatas caught up with Marcus in turn 2, and decided that the best way to get around was to with two wheels off in the dirt on the inside. Marcus tried to adjust his line to keep the Miata out of his door, and ended up agricultural way off to the outside of turn 2. I am certain if it was daytime, we could have seen the cows running for their lives. Unbelievably, Marcus didn’t get stuck, and managed to make it back to the pits, but left a large portion of his front valance and brake ducts out in the pasture with the cattle.

A quick inspection found most of the damage cosmetic, but the lower skid plate was rather loose. Sean took over the car, and went out, but we had to call him in a few laps later when the corner workers reported sparks from under the car. It turns out the skid plate was looser than was initially thought, and was dragging on the track under the car and kicking up sparks as it was being ground away by the tarmac. Hasty removal of the offending part put Sean back on the track with minimal delay.

John Neilson, Sean Neilson, and Tim Gray

Thirty minutes into his session, Sean pitted with sputtering. An initial assessment that the vent check valve was sticking allowing the cell to pressurize was proved wrong, when the check valve was removed and Sean went back out on track, the engine still sputtered in some corners. Ron added 5 gallons of fuel, and sent Sean back out on track, while the crew conferred on the likely cause of the fuel problem. A decision was made to swap to the other pickup from the cell to see if it helped. After another 30 minutes to finish his stint, Sean came in and Ron swapped the fuel cell fittings and refueled the car. And I got back in the seat for my first night session. Swapping the pickup points fixed the fuel starvation problem, as my stint was uneventful, and I ground out laps for about 80 minutes without incident. Scott Miller got back in the car for his second stint, and returned to the pit lane some 10 minutes later with his right front fender pushed in and rubbing the tire from mild body contact with a Camaro. Some quick tugging on the fender fixed the rub, and Scott went back out, and finished his stint without any incident and handed the car over to Tim.

Tim’s second stint was clean, as was that of Marcus, who went out after him. At the end of his second stint, the race was past halfway, so Marcus brought the car behind the wall for scheduled mid-race maintenance. 25 minutes later, Sean reentered the track with fresh front brakes. Some time during the night, one of the Dick Cepek offroad lights quit working, but the other was working well enough that it wasn’t a problem. Yet.

Sean had another clean run, and after 70 minutes, he came in and I got back in the car. When I fired the car up after the fuel stop, the remaining Dick Cepek off-road spotlight failed, leaving me to run my whole 70 minutes with only the PIAA apex lights. I had another clean run, followed by still more poorly lit but clean sessions by Scott and Tim, who drove the car into the first light of day.

We had survived the night, but others were not as lucky.  Professional ALMS and 24 hours of Le Mans driver Johannes van Overbeek lost a tire on the back straight and flipped his Porsche 911, totaling the car.  A Factory Five Cobra replica driven by Spencer Sharp was having mechanical problems and  made a surprise left turn for an access road, directly in front of 2007 Mazda Miata driver Johnny Kanavas resulting in a spectacular double flip off of turn five in the early dawn of Sunday morning. The 2006 Mazda Miata was a total loss as was the Factory Five racer.  Johnny Kanavas suffered a broken thumb in the crash, but thankfully there were no other injuries..

Sunrise Sunday morning

Marcus resumed the controls, and near the end of his stint, the Panhard rod broke yet again, sending the car behind the wall again for some therapy with the welder. After a short delay, we got going again, with Sean back in the car, starting the 4th and final rotation through the driver lineup. The standard 70 minute stint schedule was dropped at this point, as our position in the finishing order was unlikely to change, as there were 12-15 laps between the cars ahead of and behind us. The schedule was adjusted, to allow one more complete pass through the rotation, allowing car owner and team principal Marcus Miller to finish the race.

Tom Suited up for his final stint

As Sean’s stint was drawing to a close, I was suited up ready to get in the car for my last session, I made my normal last chance bathroom break about 5 minutes before Sean’s scheduled pit window, only to return and find him on pit lane with what seemed to be another fuel pickup problem. It seems he hit pit road as soon as I left the pit box. Luckily Scott Miller was in the pit box, in his driving gear so all he had to do was pull on his helmet and hop in the car and go. I came back to the pit box as he was getting in the car. Sean reported that during his stint, the clutch had started slipping after 3rd to 4th gear shifts.

Wrecked Miata and Cobra

About 25 minutes into a scheduled 40 minute stint, Scott came back into the pits, saying “Something broke”. Ron quickly dumped in a can of fuel and Scott headed behind the wall, where after a brief investigation, it was found one of the bolts for the transmission crossmember had fallen out. A bolt was quickly removed from the Pro-7, and I hopped in to do my last stint. Scott reported the clutch was pretty much gone. My final stint consisted of nursing the car around in 4th gear the whole time, taking it as easy as possible, as the finish was in sight, under two hours away. The rear end had also developed a very unpleasant intermittent noise under braking. I managed to nurse the car around, where I handed it off to Tim for his final session. After he was strapped in and Ron dumped the last can of fuel into the car for the race, Tim turned on the fuel pump and ignition, hit the starter button, and nothing happened. No cause of the problem was immediately evident, the fuel pump was running, and the battery had voltage, so we push started the car on pit road, and Tim headed out on track.

Tim’s final stint was essentially the same as mine, but he did determine the grinding noise from the rear was probably coming from the limited slip, as it only seemed to do it if you were trail braking. As long as you braked in a straight line, it was quiet. Tim left the car running for the final driver change, as Marcus got in the car for the final 20 minute limp to the checkered flag. We didn't fuel, so we left the car running for the final stop.   Video of the last stop (3MB WMV file)

Marcus waits for the last driver change

As the time ticked closer to zero, the crew nervously waited in the pits when Ron pointed out that every time Marcus drove by, the car was a little louder. An ugly exhaust leak had developed, and with about 10 minutes left in the race, the exhaust pipe broke in 2 pieces just behind the header, and the resonator and pipe were hanging under the car, nearly dragging on the track.

Marcus heads for the checkered flag

Marcus held out to take the checkered flag, finishing the longest closed course endurance race in the world. We finished 34th overall 13th in class, and completed 511 laps, or 1533 miles.  Of the 58 teams that started the race, only 45 were running at the finish, and some of the finishers had been parked for hours, just waiting to limp across the finish line at the end, so they could finish.  Our class had 20 teams.

Post race impound on pit road

It was a blast.

Congratulations to the Lost 'N Spaced Racing Porsche 911, who took the overall win. The second place car was the SSF BMW M3, followed by the Car and Driver Subaru.

Congratulations also to Team German Sport / Mel & Sons Muffler / Workpad.com who consisted of GTI Cup regulars Carlos Suarez, Don Bailey, and Dan Piña who won the E3 class, and finished an outstanding 18th overall in their VW rabbit GTI.  Norcal GTI racers  David Piña and Scott Neville were there as crew.  You can read their race diary here.

Thanks to everyone who made this possible.  Marcus and Scott for the Vision, Scott Lipton for organization and administrivia, Ron for keeping the car fueled without spilling a drop and keeping the timing straight, Grant, Bryan, Robert, Charles and Bob for keeping the fuel jugs filled, and wrenching on the car and everything else, Fire Marshal Sean for saving our weekend, Tim for bringing the outstanding brake parts and the warm place to sleep in the RV, John for welding the car back together twice and generally keeping it alive, Mary and Angie for keeping us in food and coffee

We are looking forward to next year.

Full results are available from NASA here.  The official NASA Press Release is here
Video of the last stop (3MB WMV file)

Photo Gallery

Csaba Csesre, the Editor in Chief of Car and Driver was part of the team in the next pit box.  They have articles, video and photos here:
http://www.caranddriver.com/article.asp?section_id=4&article_id=10379  The videos of their pit stops were taken from our pit wall.

Some strats pulled from Timing and Scoring:

Marcus had the best lap of the race, with a 2:16.6 in lap 152.

Sean's best was a 2:17.1 in his first stint, but did four 2:17.xs and
a string of  :18 and :19s in his last stint, when the car was pretty
much used up.  Of the 28 laps in his final stint, all but 4 were
2:20.x or below.  Outstanding consistency with a tired car.

Scott turned a 2:18.7, in lap 235 just past the 11 hour mark.

Tim's best was a 2:18.9, turned in lap 261, just before midnight.

My best was a 2:19.9, done in my first stint.  In daytime.

My best lap in the dark was a dismal 2:24.  Unlike Scott and Tim, I
get slower when I can't see ;-)

The panhard bar repairs cost us about 30 minutes each.

Marcus's visit to the back pasture cost us just over 10 minutes,
closer to 12 counting the second stop to remove the skid plate.

The midpoint stop to change the brakes was just under 30 minutes.

Fuel stops/driver changes added 4-6 minutes per stop.

I was about 5 seconds per lap slower in my second night stint, after
the driving lights failed.  It didn't seem to bother Scott as much as
it did me.

The transmission crossmember bolt falling out cost us just over 20 minutes.