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More Top Fuel..

More Top Fuel..

More Top Fuel..

(OP)
Found this info, interesting!

At top engine speed, the exhaust gases escaping from the open headers produce about 800 pounds-force (3.6 kilonewtons) of downforce.

*The engine will consume as much as 22.75 gallons of fuel during warmup, burnout, staging, and the quarter-mile run.

*Compression ratio is about 6.5:1.

*Air is fed to the compressor from throttle butterflies with a maximum area of 65 sq. in. 45.5 Maximum boost, in PSI, produced by the supercharger at wide-open throttle.

*Fuel is injected by a constant flow injection system. There is an engine driven mechanical fuel pump and about 42 fuel nozzles. The pump can flow 92 gallons/minute at 8000 rpm and 500 PSI fuel pressure. In general 10 injectors are placed above the supercharger, 16 in the intake manifold and two per cylinder in the cylinder head.

*Normal ignition timing is 58-65 degrees BTDC. Directly after launch the timing is typically decreased by about 25 degrees for a short time as this gives the tires time to reach their correct shape. The ignition system limits the engine speed to 8400 rpm. The ignition system provides initial 50,000 volts and 1.2 amps. The long duration spark (up to 26 degrees) provides energy of 950 millijoules.

*Power output of these engines is most likely somewhere between 6000 and 8000 hp. This is calculated from performance as these engines aren't tested on a dynamometer. This would suggest a torque output of 5100-6750 Nm (3760-4980 lb-ft) and also a brake mean effective pressure of 80-100 bar.

Ken

RE: More Top Fuel..

Here are some more. I don't know the source, in order to give credit.


* The 500-inch Hemi makes more horsepower than the first 8 rows at Daytona.

* Under full throttle, a the 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.

* The supercharger takes more power to drive then a stock hemi makes.

* 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.

* Dual electronic magnetos apply 44 amps to each spark plug. This is the output of an arc welder in each cylinder.

* At stoichiometric (exact) 1.7:1 air/fuel mixture (for nitro), the flame front of nitromethane measures 7050 degrees F.

* Nitro methane burns yellow. The spectacular white flame seen above the exhaust pipes 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 of its fuel flow.

* If spark momentarily fails early in the run, unburned nitro builds up in those cylinders and then explodes with a force that can blow cylinder heads off the block in pieces or blow the block in half.

* The engines 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.

* To exceed 300mph in 4.5 seconds dragsters must accelerate at an average of over 4G's. But in reaching 250 mph well before 1/2 track, launch acceleration is c oser to 8G's.

RE: More Top Fuel..

I think those are from motortrend.....

See thread71-141746

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