Quote:
Originally Posted by Invisable
I am building a Land Speed Racer, so I guess one might say above average.
Jim
|
An article from a Harley forum I was on called HED
> For the engineer types among us.......fascinating stuff.
>
> A Lesson in Acceleration:
>
> First, some useful info:
>
> * One NHRA Top Fuel dragster 500 cubic inch Hemi engine makes more
> horsepower than all the cars in the first four rows at the Daytona 500.
>
> * Under full throttle, a Top Fuel dragster engine consumes 1 gallon of
> nitro
> methane per second; a fully loaded 747 consumes jet fuel at the same rate
> with 25% less energy being produced.
>
> * A stock Dodge 426 Hemi V8 engine cannot produce enough power to drive
> the
> dragster's supercharger.
>
> * With 3000 CFM of air being rammed in by the supercharger on overdrive,
> the
> fuel mixture is compressed into a near-solid form before ignition.
>
> * Cylinders run on the verge of hydraulic lock at full throttle.
>
> * At the stoichiometric 1.7:1 air/fuel mixture for nitro methane the flame
> front temperature measures 7050 degrees F.
>
> * Nitro methane 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.
>
> * Dual magnetos supply 44 amps to each spark plug. This is the output of
> an
> arc welder in each cylinder.
>
> * 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 the fuel flow.
>
> * If spark momentarily fails early in the run, unburned nitro builds up in
> the affected cylinders and then explodes with sufficient force to blow
> cylinder heads off the block in pieces or split the block in half.
>
> * In order to exceed 300 mph in 4.5 seconds dragsters must accelerate at
> an
> average of over 4G's. In order to reach 200 mph well before half-track,
> the
> launch acceleration approaches 8G's.
>
> * Dragsters reach over 300 miles per hour before you have completed
> reading
> this sentence.
>
> * Top Fuel Engines turn approximately 540 revolutions from light to light.
>
> * Including the burnout the engine must only survive 900 revolutions under
> load.
>
> * The redline is actually quite high at 9500 rpm.
>
> * The Bottom Line; assuming all the equipment is paid off, the crew worked
> for free, and if,for once NOTHING BLOWS UP, each run costs an estimated
> $1,000.00 per second. The current Top Fuel dragster elapsed time record is
> 4.441 seconds for the quarter mile (10/05/03, Tony Schumacher).
>
> * The top speed record is 333.00 mph (533 km/h) as measured over the last
> 66' of the run (09/28/03 Doug Kalitta).
>
> Putting all of this into perspective for you bikers: You are riding the
> average $250,000 Honda MotoGP bike. Over a mile up the road, a Top Fuel
> dragster is staged and ready to launch down a quarter mile strip as you
> pass. You have the advantage of a flying start. You run the RC211V hard up
> through the gears and blast across the starting line and past the dragster
> at an honest 200 mph (293 ft/sec). The 'tree'goes green for both of you
> at
> that moment. The dragster launches and starts after you. You keep your
> wrist
> cranked hard, but you hear an incredibly brutal whine that sears your
> eardrums and within 3 seconds the dragster catches and passes you. He
> beats
> you to the finish line, a quarter mile away from where you just passed
> him.
>
> Think about it, from a standing start, the dragster had spotted you 200
> mph
> and not only caught, but nearly blasted you off the road when he passed
> you
> within a mere 1320 foot long race course.
>
> That, folks, is acceleration .
>
>
>