Monday, April 18, 2011

First Enduro Practice

This year I'll be co-driving a BMW M3 in the Western Endurance Racing Championship. This is series of eight multi-hour endurance sports car races at tracks in Northern and Southern California. Our team is called Boulder Creek Ring.

I attended the team's first test session of the season last weekend at the Buttonwillow racetrack in the central valley. The goal was to get some seat time in the car, gain familiarity with it's systems, and -personally- to show these guys that I can actually drive. It was a great session and I learned a lot.

These tests are chock full of new and exciting things that require the driver to adjust. For me the first adjustment was the fully digital dash in the car. No traditional tach or speedo, just a single LCD screen and a bunch of shift and warning lights. Lots of data to deal with at high speed. Using shift lights was also pretty interesting. It was hard to tell when the actual redline arrives and based on data I was shifting 500-600 RPM too early to avoid over-revving someone elses race car engine. During the second session I noticed that there is a tach-like graphical display that I found much easier to use. Later in the day I gained confidence in my ability to use the lights and shifted back to using only the lights.

The LTW we are racing this year is much like my (non-LTW) 1995 M3 so I was quite confortable as I strapped in. But, as I got out on track, there were more adjustments. I have to admit that I've never had to shift a BMW into 5th gear on a race track. All my cars have had stockish rear-end ratios that use 2nd-3rd-4th on the track, but the LTW has a lower 3.73:1 diff that uses instead 3-4-5 on the track. It doesn't sound that hard, but shifting is done without thinking so I had to retrain my hand to move up-and-right instead of straight down on the straights. It took most of a session to get used to it (and also not shifting down to 2nd for the hairpin). This car has a radio system so I got to test all the gear recently installed in my new helmet which seemed to work just fine. All my driving gear was new this year as my old helmet expired last year and my fire suit was a 1997 model.

Boy have fire suits improved in the last 13 years. My old 3-layer suit weights 6.2 lbs and feels like a heavy blanket. My new suit less that 4 lbs and feels like a windbreaker. The car also has a cool shirt system that pumps icewater into the drivers suit to keep them cool. I swore that when I took the air conditioning system out of my M3 that I would get one but never did. Now having used one, I never want to go back.

We also conducted some fuel consumption tests to accurately forecast fuel use during the events. Based on the data the car consumes about 1 gal of fuel every 5 min. This is a critical measurement as fuel use is the most critical factor during the race.

By the end of the test day I was most proud of the fact that I was able to deal with all the new gear and all the little adjustments and still get up to speed quickly in a new car. By the end of the second session I was putting up times that were competitive with the drivers from last year (not "faster than"... just "competitive with") which is OK for the new guy. I also didn't wreck the car or do anything else stupid.

On Saturday afternoon, the car's owner campaigned it in the BMW Club Racing series sprint race finishing 7th overall. Saturday night was the first Enduro of the season, a 3-hour event starting at 6:10pm. Because this is a short event I didn't drive. Tony qualified the car well, 7th overall, and we had a cleanstart. The first stint was unremarkable and after about 70 minutes we brought the car in for fuel and the only driver change. We added 15 gallons and sent Tony out for a double stint. Tony is our fastest driver and did a great job moving the car up to 2nd place in class and 5th overall with a good margin before his fuel stop.

Here is where we made a little mistake -- it actually ended up costing nothing, but it's a lesson none the less.

I radioed Tony an hour into his stint for a fuel level check he estimated that there was still 1/4 of a tank remaining so he stayed out for another 6 laps. When he pitted we only had about 30 min remaining in the race but our previously agreed-upon fuel strategy called for 2 full cans of fuel. We stayed with the plan and held the car in the pits while we added the second can and sent him out again.

When I got the first Timing & Scoring update after Tony returned to the track, I realized that the extra time had allowed the 3rd place car to close to within about 20 seconds of our car. I immediately radioed Tony to tell him and he immediately responded by trimming 2 seconds a lap off his times. I'm not sure we could have stayed ahead to the end, even with faster tiems they were gaining every lap and we still had about 15 min to go. Either way, we were in for a podium, one of our goals this year. Sadly Tony radioed in a couple minutes later and sad there was a coolant temperature alarm and he was coming to the pit box to avoid destroying the motor. Thats how is ended for us, 15 minutes to go, parked in the box.

So for the next race I'm developing a simple fuel model that tracks consumption by lap and provides data about what is in the car and about how much more fuel can fit at any time. Data is Power.

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