SolarEagle
March 12th, 2009, 21:05
This stuff is wild, and given all the Warbird fans around here I figured this stuff on Top Fuel drag engines would be of interest.......
David E. Davis, with help from friend William Neely, claims that the 500 ci Hemi (meaning cylindrical combustion chamber, not dodge) in a Top Fuel (http://www.sim-outhouse.com/sohforums/#) dragster makes more horsepower than the first four rows at the Daytona 500.
- Phillips says that a nitro-burning V-8 expends 400 of its 7000 horsepower (that's 875hp/cylinder) just to drive the supercharger. In John's words, that is "...(t)he equivalent of a Corvette (http://www.sim-outhouse.com/sohforums/#) Z06 engine just to spin the blower." Dodge's newly redesigned Hemi V-8 (in stock form) couldn't drive that supercharger if it wanted to.
- Both Phillips and Davis must be reading the same data books, because they both say the fuel mixture is compressed so much in the engine that it is nearly forced into a solid phase before ignition. With the supercharger force-feeding the engine at 3000 CFM, the engine is on the verge of hydraulic lock, i.e., it's own pistons can barely overcome the pressure exerted by the incoming air. That is, until the spark plug ignites.
- At a stoichiometric ratio of 1.7:1 air-fuel mixture for nitromethane, the flames coming out of the exhaust (http://www.sim-outhouse.com/sohforums/#) reach 7000 degrees Farenheit, or 3870 degrees Celsius. Just for a baseline, consider that Ti-6Al-4V, a widely used titanium alloy, melts at just under 1700 degrees C.
- At the initial drop of the clutch when the light goes green, 64% of that horsepower (about 4500 ponies) is dissipated as heat. Assuming SAE horsepower (0.745 kW/hp), that is about 3352.5 kilowatts. For you electronics guys, consider the mechanical equivalent of running 57.89 amps of current through a 1kW resistor and you can start to imagine the heat generated.
- Each fuel pump consumes the equivalent of 30 horsepower, which is roughly the power rating of the first air cooled Volkswagen Beetles, or a little more than twice the horsepower added by the electric motor in the Honda (http://www.sim-outhouse.com/sohforums/#) Insight hybrid (3).
- Each fuel pump flows as much as 1.2 gallons per second at 530 psi. For reference, the fuel pump for the 12v VR6 in my Jetta puts out about 650 cm^3 of gasoline every 30 seconds, or about .0057 gallons per second, assuming 0.264 gallons per liter (2). Those fuel pumps in that dragster are putting out more than 200 times more fuel than my peppy little car. Also, for the VR6, when the engine is warm the fuel pump delivers that fuel at a mere 44 psi, about 1/12 the pressure of the dragster fuel pump.
- The dual magnetos in a Funny Car deliver 44 amps to each of the 16 spark plugs (two per cylinder) during combustion. In the words of both David E. Davis, Jr. and John Phillips, one can arc weld with such current.
- If a cylinder were to fail, any unburned nitro can ignite in the cylinder and crack the cylinder head, or even the engine block.
- 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. For anyone that watches drag racing, he or she knows that this might result in the car steering directly into the wall at more than 100 miles per hour.
- One 4.73 second quarter mile run consumes 15 gallons of fuel at about $15/gallon (or more). That is a fuel efficiency of 0.016 miles per gallon (http://www.sim-outhouse.com/sohforums/#). If these were on the street, the EPA would be furious.
- At launch, Phillips says that Funny Car drivers experience about 5.0g of acceleration, decreasing slightly to about 4.0g for the remainder of the run. However, when the car decelerates, it pulls a negative 4.0g when the parachute deploys. David E. Davis claims that Top Fuel drivers can experience average accelerations of 4.0g during a run, with acceleration as high as 8.0g at take-off. These guys could handle an Apollo 13 trip around the moon without breaking a sweat.
- Using some of these numbers, a Funny Car's 4.73 s 1/4 mile run corresponds to an average speed of 0.053 miles per second, or 190.27 miles per hour. Starting from rest the driver experiences an average acceleration of 3.66g during his run to the finish (4). Coincidentally, Phillips mentions that driver Joe Amato retired from Funny Car racing when he began having trouble "...keep(ing) his retinas attached."
- A Funny Car car achieves 100 mph in 1.2 seconds, doing so in less than 100 feet. By 660 feet, the car is traveling 260 mph.
- A single pass in a Funny Car costs about $2000 per second, while Top Fuel dragsters might spend a more thrifty $1000 per second. Using the numbers from above, about $250 is spent on fuel per run.
- Due to the downforce on the front wing and the torque exerted on the chassis (http://www.sim-outhouse.com/sohforums/#) by the powertrain, the frame of a Top Fuel dragster visibly bows upward during the run.
- A Top Fuel dragster's 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). It is not unusual for an engine to be completely rebuilt after a single run.
- Finally, this is my favorite: Imagine yourself driving a $140,000 Lingenfelter Twin Turbo Corvette Z06. Holding a steady 200 mph, you pass a Top Fuel dragster idling at the beginning of a straightaway. Just as you pass, the dragster launches after you. Within 3 seconds, the dragster not only catches you, but beats you to the finish line. He passed you within 1320 feet and probably blew you right the hell off the road (7).
David E. Davis, with help from friend William Neely, claims that the 500 ci Hemi (meaning cylindrical combustion chamber, not dodge) in a Top Fuel (http://www.sim-outhouse.com/sohforums/#) dragster makes more horsepower than the first four rows at the Daytona 500.
- Phillips says that a nitro-burning V-8 expends 400 of its 7000 horsepower (that's 875hp/cylinder) just to drive the supercharger. In John's words, that is "...(t)he equivalent of a Corvette (http://www.sim-outhouse.com/sohforums/#) Z06 engine just to spin the blower." Dodge's newly redesigned Hemi V-8 (in stock form) couldn't drive that supercharger if it wanted to.
- Both Phillips and Davis must be reading the same data books, because they both say the fuel mixture is compressed so much in the engine that it is nearly forced into a solid phase before ignition. With the supercharger force-feeding the engine at 3000 CFM, the engine is on the verge of hydraulic lock, i.e., it's own pistons can barely overcome the pressure exerted by the incoming air. That is, until the spark plug ignites.
- At a stoichiometric ratio of 1.7:1 air-fuel mixture for nitromethane, the flames coming out of the exhaust (http://www.sim-outhouse.com/sohforums/#) reach 7000 degrees Farenheit, or 3870 degrees Celsius. Just for a baseline, consider that Ti-6Al-4V, a widely used titanium alloy, melts at just under 1700 degrees C.
- At the initial drop of the clutch when the light goes green, 64% of that horsepower (about 4500 ponies) is dissipated as heat. Assuming SAE horsepower (0.745 kW/hp), that is about 3352.5 kilowatts. For you electronics guys, consider the mechanical equivalent of running 57.89 amps of current through a 1kW resistor and you can start to imagine the heat generated.
- Each fuel pump consumes the equivalent of 30 horsepower, which is roughly the power rating of the first air cooled Volkswagen Beetles, or a little more than twice the horsepower added by the electric motor in the Honda (http://www.sim-outhouse.com/sohforums/#) Insight hybrid (3).
- Each fuel pump flows as much as 1.2 gallons per second at 530 psi. For reference, the fuel pump for the 12v VR6 in my Jetta puts out about 650 cm^3 of gasoline every 30 seconds, or about .0057 gallons per second, assuming 0.264 gallons per liter (2). Those fuel pumps in that dragster are putting out more than 200 times more fuel than my peppy little car. Also, for the VR6, when the engine is warm the fuel pump delivers that fuel at a mere 44 psi, about 1/12 the pressure of the dragster fuel pump.
- The dual magnetos in a Funny Car deliver 44 amps to each of the 16 spark plugs (two per cylinder) during combustion. In the words of both David E. Davis, Jr. and John Phillips, one can arc weld with such current.
- If a cylinder were to fail, any unburned nitro can ignite in the cylinder and crack the cylinder head, or even the engine block.
- 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. For anyone that watches drag racing, he or she knows that this might result in the car steering directly into the wall at more than 100 miles per hour.
- One 4.73 second quarter mile run consumes 15 gallons of fuel at about $15/gallon (or more). That is a fuel efficiency of 0.016 miles per gallon (http://www.sim-outhouse.com/sohforums/#). If these were on the street, the EPA would be furious.
- At launch, Phillips says that Funny Car drivers experience about 5.0g of acceleration, decreasing slightly to about 4.0g for the remainder of the run. However, when the car decelerates, it pulls a negative 4.0g when the parachute deploys. David E. Davis claims that Top Fuel drivers can experience average accelerations of 4.0g during a run, with acceleration as high as 8.0g at take-off. These guys could handle an Apollo 13 trip around the moon without breaking a sweat.
- Using some of these numbers, a Funny Car's 4.73 s 1/4 mile run corresponds to an average speed of 0.053 miles per second, or 190.27 miles per hour. Starting from rest the driver experiences an average acceleration of 3.66g during his run to the finish (4). Coincidentally, Phillips mentions that driver Joe Amato retired from Funny Car racing when he began having trouble "...keep(ing) his retinas attached."
- A Funny Car car achieves 100 mph in 1.2 seconds, doing so in less than 100 feet. By 660 feet, the car is traveling 260 mph.
- A single pass in a Funny Car costs about $2000 per second, while Top Fuel dragsters might spend a more thrifty $1000 per second. Using the numbers from above, about $250 is spent on fuel per run.
- Due to the downforce on the front wing and the torque exerted on the chassis (http://www.sim-outhouse.com/sohforums/#) by the powertrain, the frame of a Top Fuel dragster visibly bows upward during the run.
- A Top Fuel dragster's 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). It is not unusual for an engine to be completely rebuilt after a single run.
- Finally, this is my favorite: Imagine yourself driving a $140,000 Lingenfelter Twin Turbo Corvette Z06. Holding a steady 200 mph, you pass a Top Fuel dragster idling at the beginning of a straightaway. Just as you pass, the dragster launches after you. Within 3 seconds, the dragster not only catches you, but beats you to the finish line. He passed you within 1320 feet and probably blew you right the hell off the road (7).