ASC log 7/9/12: The Fourteenth Day

Impulse performing the braking test on wet pavement. (and failing miserably)

 

Natural selection has weeded out our most easily remedied problems, and now the most annoying ones remain. We spent literally the entire day trying to pass the brake and horn tests. However, we were able to pass the brake test eventually, and the story is pretty dramatic so I’ll tell it here.

 

So for the brake test, you have to drive the car over wet pavement and brake within a certain amount of time. A guy is waiting there giving you flag signals. When he drops the flag, then you have to start braking, and they time how long it takes you to come to a complete stop. The braking time must be at most one tenth of your speed when the flag was dropped. For instance, if you are going 30 mph when they drop the flag, then you need to stop in 3 seconds. If you are going 40 mph then you need to stop in 4 seconds, etc. So we were traveling around 30 mph consistently, and braked in 4 seconds consistently, leaving us 1 second behind – on our best runs, we would be .3 or .4 behind. We went through this test for hours, trying to perfect our braking technique. We eventually decided that something fundamental about the car must change. Around 3, we pulled off the track and brainstormed for a bit.

 

We had two primary things on our mind: tire pressure and weight distribution. Decreased tire pressure would lower the efficiency of the car, but cause us to brake faster. This is a desperate measure because dropping our tire pressure would drastically reduce our performance in ASC, but we might have to do it in order to qualify at all. The other option is changing the weight distribution, either by moving weight around on the car or adding weight to it. Since the brakes are on the front wheels, we want to put more weight on the front half of the car in order to improve our braking. Up until now, we had kept the ballast in a box underneath the driver – for our lightest driver, the ballast is about 50 pounds. If we shifted this to the front of the car, it would significantly change the weight distribution on the wheels, but this would require getting a new box and mounting it, and we were short on time since the dynamic tests are finished forever at 7 PM.

 

We quickly formulated a plan: immediately drop the tire pressure from 80 psi to 50 psi and try the braking test. This is the fastest possible solution, and the worst for efficiency. While that is happening, we send out some people to find a box of the right size and strength requirements to hold a 50 pound ballast, and when they get back, try mounting it in the front of the car to shift the weight.

 

This is when things got pretty interesting. At 50 psi, all 3 of our drivers were eventually able to pass the brake test. While we were attempting the test, we got a call from the group that went out to get a ballast box, informing us that they had rear ended someone in my car. I was annoyed, but I didn’t have time to worry about this now. Luckily nobody was hurt since it was just a fender bender, and they sat tight and got a police report. In the meantime we sent out another car on the box mission. By the time we passed the test with the low tire pressure and returned to our camp, we had a new box, and it was perfect. We mounted the box, moved the ballast to the new box, and got ready to increase the tire pressure back to 80. We figured that since we already passed the test, attempting again with a higher pressure can only help us – the tire pressure at which you pass the brake test needs to be locked in for all of FSGP and ASC, so we want to pass with the highest pressure possible. However, when we went to increase the pressure, we realized that the repeated brake tests had worn away a tire almost to the point of rupturing. We tried to replace the tire, but it took us much longer than expected – it is very hard to change tires with the limited tools that we have on hand. By the time we were able to do it, it was already 7:30 PM – dynamic testing should have ended by now. We asked around and discovered that because many teams needed more time, they had extended the deadline to 8 PM. It’s go time. We loaded up the cars, got the driver and radios set up, and headed out onto the track. We got there and had to wait in the queue as other teams took the test. We finally got on the track at 7:53 PM. We went around the track, and our driver performed the brake test. On the very first try, at 7:56 PM, we passed. We were now set to race at 80 psi tire pressure, our optimal pressure. We did exactly what we needed to do, and we are prepared to face the challenges of ASC head on.

 

But, there is still one more thing we need to fix – the horn. The horn is still too quiet, and we couldn’t work on it while attempting the brake tests. We went out and got a few new horns of various decibal ratings. In our process of testing the new horns, we ended up blowing a transistor on a key PCB. Now we need to fix that and fix the horn. It feels like 2 steps forward, 3 steps back. I had no idea how to fix this issue – this was entirely electrical and I had no idea what was going on.  If we don’t pass this, we don’t race, and FSGP starts tomorrow. We don’t need to race on all 3 days of FSGP in order to qualify for ASC; we only need to either do 105 laps on one day, or 160 laps on two consecutive days to qualify. So we are not completely fucked yet. But we are still running out of time, and I would be fucking pissed if we didn’t race because our horn was literally three decibels short of regulation. There’s nothing I can do now, and as for the team, it’s getting late – we will have to solve this problem tomorrow while other teams are racing, and hope that we can qualify for ASC in the latter two days of FSGP. As of tonight, only seven teams out of the 18 that signed up have passed scrutineering. Two gave up and stayed home, meaning that 9 teams in total are still trying to pass scrutineering when FSGP starts. These are unprecedented numbers – either the teams this year are particularly unprepared, or the regulations / scrutineers are particularly strict. I think both are probably true. Either way, it’s not a race if there are only 7 teams qualified. That’s so boring. I want at least 10 teams to be raycing for it to really be interesting. I guess we just have to hope for the best.

 

I went home and cooked pasta while electrical people tried debugging the horn problem, but eventually we all came back home to eat. We have to get up earlier than usual tomorrow, as there is a photo shoot will all of the teams and cars at 7:30 AM, and a meeting before that. We need to get some rest so that tomorrow we are fully prepared to fix our horn problem and to race in FSGP if we do.

 

Another day, another struggle. Back to work tomorrow. We’re so close! But our time is running out.

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