[Land-speed] A Lesson in Acceleration

[Joe Timney]

   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, but
   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, th e
   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 build s 
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 (most reach over 260 mph by half 
track).

   * 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 rpm redline is actually quite high at 9500 rpm.

   * The Bottom Line; assuming all the equipment is funded, the crew works
   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  (just three city blocks in 
length).

                            That, folks, is acceleration!