Top Fuel
Posted: Mon Aug 11, 2008 6:31 pm
fun facts...
A nitro-burning V-8 expends 400 of its 7000 horsepower (that's 875hp/cylinder) just to drive the supercharger.
One cylinder of the eight cylinders of a Top Fuel dragster or a Funny Car produces 750 horsepower, equaling the entire horsepower output of a NASCAR engine.
Each fuel pump consumes the equivalent of 30 horsepower, which is roughly the power rating of the first air cooled Volkswagen Beetles.
Each fuel pump flows as much as 1.2 gallons per second at 530 psi.
The dual magnetos in a Funny Car deliver 44 amps to each of the 16 spark plugs (two per cylinder) during combustion.
During idle, a Funny Car consumes a gallon of fuel every 15 seconds. Balance of weight is such an issue that if the car idles too long, it will be too light in the nose and will lift the front wheels during initial acceleration.
A Top Fuel dragsters engine can have a redline as high as 9500 rpm, but it need only survive 900 revolutions under load to complete a run. In most cases, it turns 540 revolutions from light to light (not including idle beforehand).
Under full throttle, a dragster engine consumes 1 1/2 gallons of nitro per second, the same rate of fuel consumption as a fully loaded 747 but with 4 times the energy volume.
Even with nearly 3000 CFM of air being rammed in by the supercharger on overdrive, the fuel mixture is compressed into nearly-solid form before ignition. Cylinders run on the verge of hydraulic lock.
At stoichiometric (exact) 1.7:1 air/fuel mixture (for nitro), the flame front of nitromethane measures 7050 degrees F.
Nitromethane burns yellow. The spectacular white flame seen above the stacks at night is raw burning hydrogen, dissociated from atmospheric water vapor by the searing exhaust gases.
Spark plug electrodes are totally consumed during a pass. After 1/2 way, the engine is dieseling from compression-plus the glow of exhaust valves at 1400 degrees F. The engine can only be shut down by cutting off its fuel flow.
A fuel pump for an NHRA Top Fuel dragster and Funny Car delivers 65 gallons of fuel per minute, equivalent to eight bathroom showers running at the same time.
The 17-inch rear tires used on NHRA Top Fuel dragsters and Funny Cars wear out after four to six runs, or about two miles? Some brands of passenger-car tires are guaranteed for 80,000 miles.
It takes just 15/100ths of a second for all 7,000 horsepower of an NHRA Top Fuel dragster engine to reach the rear wheels.
Dragsters twist the crank (torsionally) so far (20 degrees in the big end of the track) that sometimes cam lobes are ground offset from front to rear to re-phase the valve timing somewhere closer to synchronization with the pistons.
If all the equipment is paid off, the crew worked for free, and for once NOTHING BLOWS UP, each run costs $1000.00 per second.
Dragsters reach over 300 miles per hour before you have read this sentence.
To give you an idea of this acceleration, the current TF dragster elapsed time record is 4.477 seconds for the quarter mile. This means that you could be coming across the starting line in your average Lingenfelter powered "twin-turbo" Corvette at 200 mph (on a FLYING START) and the dragster would BEAT you to the finish line FROM A DEAD STOP in a quarter mile distance.