Drag Cars - Part 3

Getting a Top Fueller Drag Car off the line is very difficult. The driver has no fancy computer technology to help him or her.
By the way, one of the attractions of getting into the sport as a family is that you know where the kids are on a Saturday night - they're in the garage, helping rebuilt the car. And depending on the family, and each person's skills, just about anybody in the family could be the driver. There is a computer in the car, but its job is only to gather data. There is no computer helping the driver.
Just as another aside, part of the reason that a crim-kiddie can sometimes outrun the cops, even though the cops have a lot more training, is that their car is equipped with all kinds of fancy electronics, such as Electronic Stability Control. When an amateur driver is pushing one of the modern hot cars really quickly, they don't see that inside the computers, all kinds of circuits are working the brakes and transmission really hard to stop the car from spinning out. But when they do finally go out of control, they are usually travelling stupidly fast - which is why they suffer such horrible injuries as the car smashes into the landscape, or an innocent bystander's vehicle.
But the drag car drivers have no such electronic assist. They do have a (relatively primitive) mechanical computer in the clutch, to help them get off the line. Drag racing is an expensive hobby. If nothing blows up, and all you to do is the essential rebuilds and maintenance, a single run will cost you $1,000 per second - $5,000 is typical. So there's a lot of pressure on everybody to make sure that when it's time for the car to do a run, that it actually does the run, and doesn't waste everybody's time, hard work and money.
They're trying to put down 6,000 HP through the gearbox, clutch and tyres onto the road. The enormous tyres do absorb some of the shock by wrinkling up on take-off - but there's a limit to what they can do. The gearbox is nothing like a regular car gearbox - all it has is forward and reverse. The clutch is the key.
The clutch is a centrifugal clutch, that locks up in some 20-or-so separate pre-adjusted stages. These stages are set up by the mechanic on the day, to suit the driver, car, weather, track etc. A wrongly-set up clutch can easily lose a run. The clutch gets to be fully locked up about two-thirds of the way down the track. The clutch gets really hot in a few seconds, reaching temperatures up to 1,000oC. And of course, to protect the bystanders, race officials and driver, the clutch is inside a "bullet-proof" clutch "can".

The tyres don't generate full grip until they're warmed up. That's why part of the ritual of every Top Fueller run is to run over a puddle of water just in front of the drag strip, and pop the tyres loose so that they spin up a huge cloud of white smoke. As they spin, the tyres get hot enough to grip properly. Then the driver stops (say) 50 metres up the strip, and a crew member guides them backwards, hopefully exactly along the same hot rubber strips that they laid down a few seconds earlier. And then they do the Christmas-tree traffic-lights amber-green thingie and vanish down the strip.
I was lucky enough to be invited to stand in Shrapnel Alley. Right between where the cars take off are two one-metre high walls of very thick concrete, about one metre apart. If an engine blows up, I was supposed to dive down between the protective concrete wall (as if!) and watch the shrapnel whistle overhead.
One at a time, each drag car would slowly barrel past me, spitting flames from the exhaust and covering me in white rubber smoke. They burnt so much fuel, that the exhaust gases would physically push me over away from them. Then they'd reverse back and set themselves up for the actual run - which was always a complete surprise to my senses.
Of course, I had earplugs in each ear, and covered my ears with my hands - but still the sound made my chest reverberate like a beaten drug. The blast of the sound was very physical - there was no room for thinking or analysing. That's me in the hot pink Barbie shirt on the right of the photo, covering my ears as the tremendous torque of the engine lifts the front wheels off the ground and twists the body.
When I got home, the family asked what all the hundreds of black spots on my face were. It took me a while to work out that they were bits of tyre rubber smoke that had condensed into black particles all over my face.

© Karl S. Kruszelnicki Pty Ltd 2005