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Rob Liebbe
03-19-2008, 09:49 PM
My Min-Enduro Experience

Rob Liebbe

MSR – Cresson
NASA Texas
3-16-2008

I want to start by saying thanks again to all those who helped me prepare for this enduro. It was offered to us at the last minute, and when I announced that I was running less than one hour before it started I had so many volunteer to help that I was almost overwhelmed. A partial list includes Adam Ginsberg, Todd Covini, Morgan Dowdy, Michael Mosty, Marshall Mosty, Jeff Burch, Jason Love, David Love, Bob Liebbe (my dad), Clifton Winkleman, and Daron Cooke. Some of the tasks did not directly apply to the enduro but helped make sure that I had some things that I needed to also run the regular 40 minute race afterwards. There were also several people who offered support in the form of cheer. I don’t remember them all but I do recall Chris Lyons and David Donovan giving me thumbs up during the pit stop and Frank Roberts standing by the track entrance giving me the fist in the air – I took it to mean “Go CMC/AI Brother Rob!”. At least that’s what I hope he meant. I couldn’t have done it without everyone’s help.

RULES
The race was setup as a one and a half hour mini enduro for the NAMEC group. They anticipated only 3 or 4 cars in the event and NASA / NAMEC opened it up to all who might be interested. There was an enduro driver’s meeting Saturday immediately after our lunch photo session. I remember Mitch Warren also attended and maybe Todd Covini. Issues discussed included the following. Car to car weight differences was an issue initially. The NAMEC group consists of smaller sports-type cars under 2500 lbs and the safety implications of running with 3100 to 3300 lb sedans was a concern. We discussed the fact that CMC used to run with Factory Five Cobras and Catherams for heaven’s sake and that extreme care and respect would be used during the race. This lead into a discussion about aggressive driving and sprint mentality vs enduro mentality. No crazy passing was to be tolerated. We also talked about vehicle to vehicle speed disparity as one of the sports cars would be running 15 seconds a lap faster than a CMC car. The sports car stated that he would run with his headlights on for visibility and we promised to be very mindful of his approach. The CMC cars were going to require fuel, so pit stops were discussed. All cars were required to make a pit stop with a minimum five minutes starting when the wheels stopped rolling. The drivers were to be required to be out of the car during refueling but this was changed during the first part of the race and was communicated to me by radio in the car. The refuel person had to be wearing the same level of protection as the driver, a fire extinguisher man was also required to stand by, and there was to be no fuel spillage allowed with extended pit time as a penalty. The fuel spillage prevention was handled by a catch pan placed under the fuel filler area. No other work was allowed on the car while refueling. Tire changes etc. have to wait until fueling is completed.

CAR PREP
Fortunately, there was some pre-warning of the event and I was able to do some prep including an oil change before leaving Houston. I also knew that I had enough parts and pieces to run the regular weekend and the enduro, specifically brake pads, tires, and wheels. Going into the weekend the front brakes had about 1/3 pad on them, the tires had maybe 4 events on them but I had fresh sets of both tires and pads with me. I also made sure there was enough fuel in my paddock to run the enduro and the 40 minute race. Overall my car is reliable and rugged and I had every confidence in its ability to go the distance.

INTENTION
I have always wanted to run for an extended period of time in the car to test myself and the car. I always felt that I would do well, but you never know until you try, and this was a great opportunity to do that and learn a few things in preparation for the upcoming 4 hour at TWS in April. I also wanted to try to learn how to pace myself instead of running the sprint pace that we are used to – not that anyone is going to pace themselves in April.

THE RACE – The first 50 minutes
The entries ended up being three sports cars, two spec Miatas, and me in my CMC Fox Mustang. The start was a staggered rolling start with the sports cars taking the green flag about two turns ahead of me and the Miatas. I started behind the Miatas and kind of planned to just stay with them for a while, but tired of that and had passed both of them of the by the completion of lap 2. My goal then was to stay ahead of the Miatas and stay out of the way of the sports cars. Somewhere during this part of the race, David Love was on track in his AIX Camaro but I think he retired early with mechanical problems. He was running even pace with me but ½ lap behind or in front so we didn’t get to run together at all.

I forgot to ask anyone to watch lap times, but by about the 6th or 7th lap were had a stopwatch going and determined that I was running CMC sprint speeds and crew chief Adam Ginsberg advised me to slow down. SLOW DOWN – Imagine that!!!! So I tried to calm down and conserve the car and tires and settled into lap times that were about 1 ½ to 2 seconds slower than sprint. The slower speed and clean air really helped keep the engine cool and let my aero package work well. I found that I could run a comfortable pace for a while and then kick it up a notch and run two or three sprint laps when I wanted to.

I was going to run until I had ¼ of a tank of fuel left and then come in for my pit stop. Everything was going well at about 45 minutes into the race and I decided that I was going to stretch the fuel stop so that we would have less chance of fuel spill. We were only going to put 10 gallons in so I wanted to burn down to below that level. Plus, I was feeling good behind the wheel and figured I could go longer. There was also a change in the driver getting out of the car during refueling requirement along in there sometime which made me happy. The tire gods intervened and decided that now was a good time to blister the outside shoulder of the RF tire, so the pit stop became fuel, RF tire and ice and water for the cool suit. We pitted at about 50 minutes into the race.




THE PIT STOP
The hot pits are short at Cresson so it wasn’t hard to see the crew, especially with so few cars running. I exited the track and drove slowly to avoid any speeding violations. The pit stops were unrehearsed with me giving Adam information through the radio. If I remember correctly, Marshall Mosty fueled the car with someone assisting with the catch pan. Marshall can fill in some details, but he prevented a fuel spill by redirecting fuel into the catch pan with his hand – nice!! I think Michael Mosty was the tire changer and did a very nice job despite my ARP lug studs being cut off and hard to start the nuts on the threads. I don’t recall who added the ice and the water to the cool suit container – sorry. Somebody also handed me a bottle of water which I drank through the eyeport of my helmet and then threw it out the passenger window hitting the official who was timing our stop – sorry!!!!!! No penalty was incurred. It all felt very professional and very cool. Everyone worked quickly, but it wasn’t rushed to the point of making mistakes. Once the work was completed we had used 6 minutes of time. I wanted to do a burnout leaving the pits space so upon getting an all clear from Todd, I revved the engine, let out the clutch and the car just launched. It’s amazing how much more grip the rear tires have with that much heat in them – duh. Out of the pits and onto the track we go.


THE RACE – The last 34 minutes
The RF tire was new as in still had mold release on it except where it had been shaved. And it was cold. I almost ran off the track on the first left hander. So I slowed down and scrubbed that tire in a bit before running hard again. When it did get warmed up, the new RF tire had more grip than the other three older tires and the car’s balance was changed on left hand turns with the good grip up front and less grip out back, the car wanted to rotate. Something to be aware of. About two laps in, something on the RF popped and there was a vibration at wheel frequency. I was afraid that the wheel was loose, so I radioed in that I was coming in to have the RF lugs checked and the tire inspected. It felt better by the time I came around Big Bend and was approaching the pits, but since I wasn’t in this for the race, I came in anyway and Michael checked it out and gave a thumbs up. I think that this is when the red and white Miata must have gotten past me. Turns out that cost me a third place finish. All clear, head out of the pits, but had to stop as the blue Miata was coming on track and I gave him the right of way. Stayed with him for a while, eventually passed him, he followed for a while and could keep up in the turns, but I was able to use my horsepower advantage to get away. I remember thinking that this must be what it was like to drive an AI car amongst the CMC cars. The race went on with the really fast sports car lapping me every so often, I just got out of his way. There was another sports car that I could out power, but not out maneuver that I ran with for a while. The third sports car was not very fast and only lasted about three laps at the first of the race and then left. With about 5 minutes to go, Adam radioed that I only need to pass one car to get a podium finish! It was the red and white Miata running about my lap times, but ½ a lap ahead. I could have never caught him. Damn me and my extreme caution and that second pit stop.

I found that I could establish a rhythm in the car for multiple laps, the slower pace was comfortable, but I did begin to get tired with about 15 minutes to go. I could get distracted and lose concentration easily. I remember Adam coming onto the radio as I was exiting Rattlesnake and heading down the hill. He asked how the car was doing and I dropped two wheels off the track. Car was fine, driver was not. No radio transmissions when the car is in a tight section of the track. Speaking of radios, Adam loaned me his setup and I was very glad to have it. We did not run an externally mounted antennae. This would have improved the signal quality I’m sure. I only used an earbud and it was fine as long as the signal was strong enough and free from static.

White flag came out, and I was glad to see it. Last lap was taken carefully so as to not do something stupid and I took my first enduro checkered flag!!!!!!! Turns out that I am the first Texas CMC Enduro participant. Al and Todd don’t count as they endured in California.

IMPRESSIONS
This will be a little disorganized, but here we go.

I’m very glad to have done this.

The car ran flawlessly for the entire event. It even started after the pit stops. Sometimes my car has a hard time starting if it is hot. In this event, the engine temps ran right at 190 degrees. In the 40 minute race the engine ran at about 210 degrees. I do not currently run an oil cooler, but may install one for the 4 hour enduro.

I burned 9 gallons of gas in the first 50 minutes and 5 more gallons in the last 34 minutes. I probably burned about 9 gallons in the 40 minute race but I haven’t measured it yet.

I blistered one front tire most likely to overdriving and the fact that I run a lot less negative camber than most of the Mustangs.

In the last two or three laps of the race, the brake pedal started feeling a little soft. I thought they were hot, so I slowed down a bit to cool them off. I do not currently run brake cooling duct, but may install them for the 4 hour event. Turns out that the front pads were just getting down to the metal at the end of the event. I think that fresh pads would go the full four hours, but be prepared in case they don’t. I run Carbotech XP 10 on Crown Victoria rotors in the front and Carbotech XP 9 (I think) on 94 Mustang GT rotors in the back. The brake bias is set to full front.

To prolong the effectiveness of the cool suit, I would run it for a while and then cut it off until I felt I needed it again.

The weather for this event was nearly perfect. The ambient temperature was near 70 degrees, the sky was clear, no rain. Be prepared for hot weather. Be prepared for rain. I will have functioning windshield wipers and rain tires for April.

I think that if the temperature is 85 degrees or above, that one hour in the car would be optimum with a driver change at the fuel stop. This would prevent fatigue a enhance safety. I probably could have gone two hours, but was getting tired near the end. But hey, I’m 41 years old and not in great shape. You young punks could probably go all the way without breaking a sweat.

There was virtually no traffic in this event. It was a stark contrast to the intensity that followed in the 40 minute race. I can’t imagine the intensity of our sprint races can be sustained for an extended period of time. I also don’t see any of us slowing down to an enduro pace. This is a concern that I have for the upcoming event. Just how many times can Burch lap the CMC field in 4 hours?

Crew – seems like a minimum of three crew members plus drivers would be required. This would include a crew chief, a fueler, and a fireman. Two more tire changers would be next on the list.

I think that NASA official learned a bit from my experience and will be taking this forward as they prepare for April.

I was being called Ironman after all of this. Ironman is David Donovan for his string of event participations. I will accept enduroman or the regular slanders that are usually used when referring to me.

OK – enough as this might qualify for the longest single post. I hope you made it through this far. I also hope that those who helped and participated will chime in with their thoughts. Again, thanks to everybody, including my wife who allows me to enjoy this hobby.

Open for discussion


Rob Liebbe
CMC #1
NASA Texas

marshall_mosty
03-20-2008, 06:54 AM
Rob,
I too had an exceptionally good time as fuel man on your enduro crew. It was amazing how quickly the time went by from the pit wall. However, the 3 minutes to put 10 gallons in your car felt like an hour!

Good job, "Enduroman"!!!

mitchntx
03-20-2008, 07:30 AM
Rob, thanks for the insight.

I wimped out, claiming tires. In reality, I had just came off a week long battle with the flu and just wasn't up to it.

AllZWay
03-20-2008, 08:12 AM
Great job...

Wirtz
03-20-2008, 08:54 AM
Great post Rob, thanks for all the insight and congrats on the run.

How was the visability of a low slug sport racer as seen from one of our sedans. I have not run an enduro in a CMC like car, and wanted to know your thoughts. For them, the high point is the roll hoop, which is typically not very large. At the enduros I have run in the past, I've seen some that put bright tape on it, or attach things like a tennis ball on a stick to roll hoops try to make the visability higher and brighter, but I don't think there is a requirement for it.

Jeff

michaelmosty
03-20-2008, 09:23 AM
Awesome write-up Rob!! Helping out on the pit crew was a blast. We all discussed our roles and sequence of events prior to the pit stop and it helped greatly. The main focus was to stay calm and take it easy b/c 5 minutes is plenty of time. It turned out the time goes by very quickly. :)
The only area we could have picked up time was to bleed down the new tire prior to install. We thought we had everything covered but obviously forgot about that. Completing the pit stop and watching Rob peel away was great, I had an awesome rush watching him take off!!!

One thing I would change is the safety requirement for pit crew. We were told that the fueler needed full gear but that the other crew member didn't have to wear a helmet while over the wall. The decision I made was to not wear a helmet while over the wall. I even overheard other teams questioning this during our pit stop. The pits were very quiet during this enduro b/c of the few participants but it just didn't feel 100% normal without a helmet. I will definitely wear complete gear with helmet while over the wall at TWS.

On a funny note, during the beginning of the race Adam told Rob he was running at a sprint pace and told him to slow it down. Rob came back and said he was going to slow down to a 1.28.xx. The next lap by he ran a 1.28.4x. Adam and I just looked at each other and laughed, Rob is a machine!! :lol:

Congrats Rob, I was glad to be a part of it, Thanks!!!

BryanL
03-20-2008, 12:41 PM
Rob,
Glad the enduro went well and you enjoyed it. Really appreciate you taking the time to provide us with the great race report.

Curious how you knew the RF was blistering? What about the tires lasting for 4 hours at TWS? I think I saw that you are only allowed 2 tires for the 4 hour. Do you think you would have to slow down even more to make the tires last?

Bryan

michaelmosty
03-20-2008, 01:06 PM
Bryan,
One of the main reasons for the blistering is the lack of camber that Rob has on the front of his car. I am guessing it is around -2degrees. This overheated the outside edge of the tire up much more than the rest of the tire and resulted in tire damage.

Once Rob gets off his butt and puts on SN95 control arms he will be able to get more front camber (around 3.5 depending on preference) to help cure the problem. Not to mention get even faster. :evil:
He also has extra weight on the front of the car b/c his battery is still up front!!

ShadowBolt
03-20-2008, 02:22 PM
Bryan,
One of the main reasons for the blistering is the lack of camber that Rob has on the front of his car. I am guessing it is around -2degrees. This overheated the outside edge of the tire up much more than the rest of the tire and resulted in tire damage.

Once Rob gets off his butt and puts on SN95 control arms he will be able to get more front camber (around 3.5 depending on preference) to help cure the problem. Not to mention get even faster. :evil:
He also has extra weight on the front of the car b/c his battery is still up front!!


I don't think we need Rob to make his car any better!

JJ

David Love AI27
03-20-2008, 06:13 PM
Great post Rob, thanks for all the insight and congrats on the run.

How was the visability of a low slug sport racer as seen from one of our sedans. I have not run an enduro in a CMC like car, and wanted to know your thoughts. For them, the high point is the roll hoop, which is typically not very large. At the enduros I have run in the past, I've seen some that put bright tape on it, or attach things like a tennis ball on a stick to roll hoops try to make the visability higher and brighter, but I don't think there is a requirement for it.

Jeff

I also ran the enduro and was given explicit instructions to watch my mirrors due to the fast closing rate of the sports car racers... since the field was very spread out I had plenty of time to check the mirrors as requested... it might have been harder if there was more door to door competition... I jumped in at the last min. and even joined the race after it had started... my purpose for participating was to break in a brand new motor so I was taking it easy and short shifting...

thanks Rob for the detailed writeup... I will be reviewing it numerous times to get an idea of what to expect at the TWS event... The LiiR team will enter the AIX 27 car with Jason Love, Nick Runyon and myself as drivers... Anyone interested in crewing should PM me for duty assignments and pre race prep and race strategy....

Rob Liebbe
03-20-2008, 08:02 PM
The low slung sports cars visibility was not a problem in this race, but like David said, it might be more difficult with more traffic around. This was a concern back when the Catherams were in our race group, but visibility wasn't the problem with those cars. It was more of a driver problem.

Recognizing the tire blister has come from experience as I have blistered many tires over the years. It my be hard to believe, but I tend to overdrive the car. :shock: First, the tire will start to go away and have a bit less grip. In this case the car started understeering on left hand turns as the RF tire started to get overheated. Second, the tire will start to vibrate and thump as the blisters go around as the tire rolls. This is prevalent in turns that load the blistered edge of the tire. If just the edge is blistered, then the vibration and thump will go away in the straights when the edge is not loaded.

Tire wear will be an issue, better have extras. I don't remember that we are only allowed two fresh tires for the entire event. I thought it was only two tires allowed to be changed per pit stop with no limit on the number of pit stops. I'll review the rules and have plenty of "slicks" and "rains" on hand.

The fueling will go better at TWS as I will have a new pair of jugs. 8)

I think that helmets for everyone over the wall is an excellent idea, especially if the pits are more crowded.

Not presetting the fresh tire pressure was indeed an error. I just overlooked it and remembered as Michael was installing it on the car. I would have ended up with a tire with about 30 - 35 psi cold. That would have been less than ideal for sure.

I hope all of this is helping.

Rob

Boudy
03-20-2008, 09:36 PM
Thanks for the write-up Rob. I hate having missed the first enduro. Sounds like it was a blast for all.

Boudy